Can i buy a sim on a plan, and put it in my phone?

[GeorgiiaBabby ,]

Well i already have the phone i want, but i want it on a plan now.
Can i buy a sim on a plan, like $30 a month, and just put it into my phone?
Thaakks
x

 

[Craig]

yes u can buy them all u do is go into the shop and ask them to put u on a plan that u want