Chosen Solution

I have an iPhone 7 with a badly cracked home button, but it still functions, so it works to go to the home menu. Can I replace the glass only?

It is not possible to replace just the face of the button as the sensor chip is fused with the face crystal.

If you already don’t have the touch ID working, you can replace it with a bluetooth return to home button. They are not great quality but they work. AFAIK the original home glass button can’t be replaced.