Let's start this off with the obvious, your story needs a hero, or at least someone who is your main character that may happen to be the hero. Your protagonist will be the backbone of your story, whether it's told from their perspective, told around or about them, or their entire existence and purpose is to be the solution.

Now let's make one thing clear, your protagonist doesn't have to be your main character (or vise versa, your main character doesn't have to be the protagonist). Your protagonist is the good guy. They're the hero of the story. But they may not be what the story is about. This chapter is just assuming that they are, I just want to be clear that they don't have to be.

If your main character isn't a protagonist, I'll be writing an antagonist chapter later.

Let's assume you already have your story in mind (and maybe you don't, that's perfectly ok):

-Your protagonist/s must have a strong desire, which likely props up the plot of your story in which you will be telling.

-Going along those lines, your protagonists actions must be what drives your story and plot forward.

-Your protagonist must make choices that should affect the story. These could be life changing choices or simple ones that affect how everything plays out in the end. Your protagonist/s are your biggest influence on the plot.

-They're your main character, and likely have an obstacle they must overcome. If not, then make one. And this goes beyond the main conflict of your story. This could be working through childhood trauma, or something simple like learning how to drive a car. It'll make them more believable and/or relatable to your reader.

-They are the good guy, but that doesn't mean they always make good decisions. They don't have to be pure and innocent, heroically a good person without a single bad bone in their body. They have flaws, they mess up, they make mistakes and choose the wrong path. That's what makes them a better protagonist.

-Why are they good? We're they raised in a bad society and they want to make a change? Or is it just in their nature? Perhaps your protagonist wants to change the world. Or, maybe they were forced to save the world against their will via a prophecy or command.

-If the story is told by them, (first perspective), allow them to explain and perceive things differently than what they really are. In other words, let them misunderstand something but don't allow the reader to know that.

-Give them flaws. Again, they can't be a perfect Angel. They can be selfish, rude, sarcastic, snobby, lazy, egotistical, mean, etc. That won't stop them from being the hero.

I'm going to pull an example from one of my own protagonists, Herogi (Land of Armonia).

Herogi lives in a fictional world where magic is real and your typical supernatural things can happen and be normal. She's a part of an indigenous culture in a mythical land that's on the brink of war.

This war is the focus of the plot in my story. The goal of ALL the good sided characters is to try and stop it and unite the people of the land. But Herogi in particular, while stills sharing that same goal, feels a little different about it. You see, to Herogi, saving the land makes her look like a hero. It makes her the good guy and earns her respect. It also would prove that she's what she believes she's cut out to be. It's all about her image. If she were in a present real world setting, she'd be the type of person who films herself giving money to a homeless person and posting it online for clout.

This is because Herogi is selfish. She's got a tall ego and acts slightly narcissistic. She's not a bad guy, she does have good will, and she also wants to save the land from destruction. It's her reasoning behind that which sets her apart and gives her a flaw which she must overcome.

The story is not narrated by Herogi, but the story telling follows around strictly her and one other main character. Sometimes it must switch from chapter to chapter if the two are not near each other or I must explain different thoughts characters may be having. Being able to do that really puts a weight on her flaws in which the other protagonist doesn't share. While the other protagonist's goals are to keep people from suffering and to protect the land, Herogi's are completely self oriented.

But they both achieve the same meaning which affects the plot and drives the story. That's what the protagonist is and should be, unless they are not your main character and your main character is the antagonist.

Here are some well written protagonists in media (in my opinion):
-Katniss Everdeen (The Hunger Games) (Flawed, story is told through her, you get to hear her wants and desires, she's well rounded)

-Lauren Sinclair (Purple Hyacinth on WEBTOON) (Has very obviously set goals, portrays a hero/protagonist who may do bad/illegal things for an overall good cause, isn't too powerful in terms of her potential)

-Peter Parker (MCU) (relatable, has his own issues which affect his choices which are often affected by his own wants and desires, has a heart of gold but pressures himself to protect and save everyone)

-Aang (Avatar; The Last Airbender) (he's young which often leads to him making childish choices, he has realistic responses to dealing with too much pressure and stress ((especially being a child)), he's got flaws that don't sound like they'd be flaws such as being TOO loyal)

-Percy Jackson (Percy Jackson and the Olympians) (learns things as the reader learns them, doesn't usually hold the burden of whatever conflict there is entirely on himself, isn't afraid to ask for help)

Here are some examples of poorly written protagonists (in my opinion):
-Yuji Itadori (Jujutsu Kaisen) (a bit overpowered, accepts things as normal very quickly when they are in fact far from normal and should take time to process, was overpowered even before he gained the abilities of Sukuna) (I still love him though, his personality makes up for all that)

-Rey (Star Wars) (Overpowered, never actually got character development, had very blurred/unclear goals, she had to much power for the amount of time it took for her to learn it in comparison to the other Jedi)

-Captain Marvel (MCU) (Also overpowered, didn't have much of an impact for how powerful she was which kinda made her seem like she either didn't care or was only thrown into Avengers Endgame for a badass female moment, doesn't have a clear motivation) (but in her defense, she had some really good scenes and in her individual movie her character was relatively ok. It was Endgame that made her seem like she thought she was above everyone else, or like the problems of other people didn't matter to her despite what her character is supposed to be about)

Questions or anything you'd like to add? Don't be afraid to make a comment!