Being a pixel owner myself, I've been tracking pixel issues, and given that history I can be fairly confident in saying you have two separate issues.
The first one, the camera issue, is usually caused by the failure to remove a piece of protective plastic coating from the lens itself on the inside of the display. Unfortunately, the only way to fix - or even verify - the problem is to take the screen back off.
As far as the fingerprint reader, all I can say is, if you figure it out there are a lot of other people who would like to know that same answer. I'm fighting with a Pixel 6 Pro with exactly the same problem. When people have been able to get it working again, they've used the Google calibration tool as described in this question.
SOLVED: Fingerprint scanner not working after replacing screen. Pixel 6 Pro - Google Pixel 6 Pro - iFixit
Your best bet is to run the calibration tool; I've done that on the phone I'm working on, but it hasn't helped me. I bought a replacement fingerprint sensor and have been trying to get help from the manufacturer; their only suggestion so far is to put the replacement sensor into the original screen and set a fingerprint to "activate" the sensor, then move it to the new screen and it should supposedly work at that point. That doesn't work for me because I don't have the original screen; it's already been replaced once, and the fingerprint sensor hasn't worked since that first screen replacement.
Anyway, give the calibration procedure a try, along with any other suggestions you find in that post, then be sure to come on back and let us know what you find. The more data we have, whether it's a success or a failure, the better chance we have to figure this blasted thing out.
Update: July 23, 2025
The fingerprint issue has been such a problem for so long that iFixit came out with a guide specifically for the calibration procedure. Note that it may require multiple attempts in order to work, so if at first you don't succeed, try, try, again.
How to Calibrate the Fingerprint Sensor in your Google Pixel Phone - iFixit Repair Guide
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I have fixed my finger print sensor by using the calibration tool.
However my front camera is black. Can you take the screen off and put it back without getting new glue?
crwdns2934271:0crwdnd2934271:0 David Robert Stockford crwdne2934271:0