My honest opinion is don’t bother, sell and get something better, even if it is a project gun.
I really cannot rate or recommend Nuprol guns for anything.
If you want a project gun, can I recommend you find a receiver(eBay or here) , and a gearbox from @ak2m4 and then do everything you want to learn with that box, upgrade little bits at a time, try whatever you want.
I did this myself, and my scratch built project gun is now the only gun I like using.