Ways to make this possible? 2 buttons pressed at same time?

This isn't a request. I've been trying to do this for about an hour now, and I've had many ideas, many different plans but I cannot quite figure out how I would be able to do something like this. Like I said, I don't want a script, I just want to know if there's 2 parts, and 2 people are pressing the individual parts at the same time, what would be a good idea to figure this out? Thanks!