I tried and i failed, so I need help on like how to make a gui with an equip and unequip button for weapons and how you keep them quipped on death kind of like mm2 or zombie rush..
Due to the fact no code was given, I'll just tell you a way you could go about doing it.
This is rough and not at all efficient, but just a way you could go about doing it.
Make a DataValue folder within the Player when they join. Within that they could have a Boolean Value stating what gun they currently have, if any.
When you click "Equip" on a gun within the UI, make the value change to the name of the gun. After that, you could have a RemoteEvent fire to the server what gun you have chosen and to clone it into their starterpack.
Make a seperate script that detects when a player dies. Once their character loads back in, make it so the server script clones the gun into the inventory once again. This can be easily done by checking what gun is in the Boolean Value and cloning it from a folder.
As I said before, this could probably be made more efficient, but it's a rough idea of how you could go about it.
Search up RemoteEvents, Cloning and values on the wiki to try and find out more.
Hope this helps!