The back of my phone broke

That depends on model iPhone you own. The back can only be replaced on the following iPhone models:

iPhone 12, 13, 14 or 15.

If you own one of these models, check this link --> iPhone Repair & Service - Apple Support

If you don't own one of those models, the entire phone needs to be replaced as Out of Warranty, unless you have a valid AppleCare+ Plan.

Start here: iPhone Screen Repair & Replacement - Apple Support

jahniya224 Said:

"The back of my phone broke: I was cleaning and I set my phone up and it fell and hit hard on wooden floor and broke the back of my phone and I need to know how much would it cost to get the back replaced"

-------

For future reference...

Look into using an OtterBox, to avoid instant damaging of an iPhone. I use one, and you may want to consider the same.