I am new to modding and for practise i wanted to make a mod that adds variations to vanilla mobs, like how zombie villagers and husks are a variation of zombies, and how strays are a variation of skeletons. However i couldn't find any information on this anywhere i have no experience at all with modding so i would appreciate some tips about how to go around doing this. Ta
Those variations are classes that extend the normal one. For example EntityHusk extends EntityZombie. This is normal Java (or object-oriented) programming technique where most of the functionality is contained in the parent class and the variations are created in child classes.
So you just need to make your own class that extends whatever you're trying to change, and override the methods that control what you want to change. Then you need to register the entity (along with its model and textures and sounds and such) like any normal custom entity.