How do I do a point system similar to Harry Potter?

So basically, I'm going to have x number of groups that will all start at 0. I know you can set it to add 1 to each group via a global variable. But this is for a teacher friend, so what I need to be able to do is this:

Teacher in virtual class tells student they have been awarded 7 points. Student logs into game and selects their group and which subject/class they are in, and enters the number of points they've been awarded. That's the number I want to add to the global variable for the total group points.

Does this make sense?

If you need different instances of your game to communicate information to each other or a central server, you're basically making a multiplayer game.

You can use messages to send information between host and peers via the official multiplayer plugin, or use a third party backend like firebase or photon or something, although that's probably overkill.

I recall seeing something mentioned recently about linking to Google Sheets, but I'm not sure if that was read only.

In general though, the specific application you are describing seems like it should be handled by a simple webpage, rather than an html5/construct game.