how do i add weaopns in roblox studio?

i need help i cant add guns or weapons in my world when i add them i can see the guns in roblox studio but if i log in my world they are not there were i put them i trad to add weapon spawner it inlanid some weapons but it stald doesit work i log in but they didit spawn can someone help me to add weapons plus plz someone message me on my roblox profile