A Birthright is a special gift granted to a Scion by a god, usually their own divine parent. If a Scion comes under the patronage of another god, which frequently occurs with gods who are unable or unwilling to reproduce the traditional way, they may also be granted Birthrights by their new master.

The idea of the Birthright is to allow the Scion to raise themselves into Legend by performing daring feats and tasks impossible for ordinary mortals. These abilities are granted in a number of ways, but arguably the most powerful Birthright are Relics, which a Scion must use, at least in the beginning, to access the godly powers called Purviews. As the Scion grows in power and Legend, they come to rely on these artifacts less and less and become accustomed to accessing their Purviews directly.

So basically these Birthrights are how you use your powers and it can be anything as long as it makes sense coming from the certain god or goddess you pick if you need help I can gladly give you some Relic idea's.