I need to restore my iPhone SE after installing new battery. How do I do this?

The battery was replaced at the Apple Store or an authorized Apple Service shop, correct? It would be up to the shop to return the phone to you in working order. Take the phone back to the shop.

Now, if you are saying that you yourself tried to install the battery, you installed the wrong battery because Apple does not sell genuine batteries to users unless they also install the battery as well. Because the phone has been tampered with, Apple won't touch it now, so you will have to try to find another shop that is willing to work on the phone.

I'm sorry, but we cannot help you.