Can I replace my white iPhone 7 cracked screen with a black one?

You can just buy one.

https://www.amazon.com/Latest-Replacement-GVKVGIH-Assembly-Version4-0/dp/B07S1Q8TL7/ref=sr_1_3?keywords=iphone+7+black+home+button&qid=1662681673&sprefix=iphone+7+black+home+%2Caps%2C144&sr=8-3

I have a 7+ and replaced the old white screen with a black one and had no issues. Just remember to buy a black home button as well.

the fingerprint button from i know you can't buy it again...

you make this ?