Can i use PKHex to change my save data? (ps. where can i find the .sav file?)

[H1mSRad]

I wanted to change my save data so i can get some pokemon early (i.e. Scythor, which is behind gym **13** for some reason)
and also to get some items, and stuff.

 

not much to say, just want to get an answer 
:D