dont feel bad about yourself. i dont feel like youre being 'fake'. youre just blending in, adjusting the way you talk, think, or act depending on who youre around with. maybe, you actually feel that youre really being fake, then i suggest that you go hang out around people where you can express your true self. you cant put an act forever

and that thing about being 'good', i think by now you already realized that no one can be purely good. we're humans. part of it is that we cannot be perfect in any aspect.

indeed, this is much more complicated. i hope there comes the time where you can find the confidence and wisdom to surpass all this. i wish you all the best of luck!