I am unable to update my Apple Watch because I forgot the passcode. How can I restore it?

If you forget your Apple Watch passcode

I am unable to remove my watch band by pressing the button on the back and sliding it out

Why do you need to remove the watch band?.

How do I get my watch band unstuck so I can remove it. I have a series 7 Apple Watch.

Just undo whatever type of fastening the band has,you don't need to remove the band from the watch.