Hi my name is ***** ***** to Just Answer. I am reviewing your question and will reply ASAP.
First of all Force Quit Photos. Press Command-Alt-Esc and click Photos and Force Quit.
When Photos is closed, restart your Mac.
When you have restarted the Mac, click Finder. Click the Go menu at the top of the screen and click Pictures.
Select the item called "Photos Library" and press Enter on the keyboard.
Rename "Photos Library" to "Photos Library old" and press Enter again.
Next try to open Photos and see what happens. The library will look empty if it opens, just get back to me with what happens first.
Were you able to Force Quit?
You're very welcome. It might not be necessary to do the remaining steps, but having a backup is very important and I would strongly recommend it. There are many ways to make a good backup. If you'd like to get back to me to ask about that please do.
The further steps were if Force Quit did not give you access to Photos again. That's something I thought might happen if the library was damaged. You should have a Photos Library in your Pictures folder. Click Finder, then the Go menu at the top of the screen, then Pictures. It should be one of the items in the list.
I don't see the need to do remote assistance, there would be an extra charge but I don't think it is necessary.
As long as you can find the "Photos Library" in the Pictures folder, then the job is complete. The only remaining thing I would recommend is some form of backup. You could easily do that with Time Machine and an external USB hard disk.
Let me know how it goes finding the Photos Library and if you have any further questions.