I have an iPhone 7 it had a new screen fitted after that it get stuck

iPhone 7's have a bit of a history of problems with the front camera/sensor assembly that can cause boot/boot looping problems. If you switched the front camera assembly from the original screen to the replacement it's possible it got damaged in the process and is causing your problems.

Easiest way to check is to simply unplug the camera and see if the phone boots up normally. Follow the front camera replacement guide up through step 15 to get the screen off then skip to Steps 20 and 21 to disconnect that assembly.

iPhone 7 Plus Front Camera and Sensor Cable Replacement - iFixit Repair Guide

Power it up and see if it works. If so, you've found your problem and can order a replacement part.

Out of curiosity, did you replace the screen yourself or hire someone to do the job? If it was a professional shop you should consider getting them to stand behind their work and fix the problem.

Otherwise you still need to figure out what's going on with the phone. I'm conflicted on the replacement screen because as the part that got replaced last it's the most likely suspect for causing the problem, but on the other hand it's fairly unheard of for a defective screen to cause a hang at boot.

Presumably the battery was unplugged during the process of changing the screen and there's always the possibility that the connector was damaged or possibly one of the components mounted next to it got knocked off and is causing the issue, so check the connector and the parts around it for any issues such as bent pins, torn cables or missing components.