Use the default gun model to make:
Right click iron sights
Shotgun
Ammo (7 shots)
Hold to rapid fire
Deagle (more damage, slower rate of fire)
Pistol whipping as right click
Incendiary ammo gun
A gun that you can throw
Laser pistol
Adding recoil to player aim
They are all decently hard to make, you need no models that are not already provided, and you can re-use your code if done properly
Good luck! I don't suggest releasing any of these unless you get a legitimate model
The best way to Learn is to rip apart other Add-ons
Findlocalclient().player.getmountedimage(0).dump(); is your friend
Coding help is a last resort, ask a friend to help you if possible