Over used words is one of the main problems while writing.

To avoid it think about it like this;
Eating the same plain icecream with no cone over and over again.

You have to take interest. Learn from amazing books outside of wattpad. There is so many dictionary words to use.

But the problem is to use many other words, your writing has to have no grammatical errors. Yes there may be little bit errors here and there, but there is a reason to proof reading and editing things that does not seem right.