Alone with your mind

Read (or listen to) a book.

I mean, I get it. But it's sad that folks have forgotten about simple shit like going outside, looking at plants, reading, drawing, thinking up puns, etc

Make something, stop doomscrolling, do something with your time that will be lasting

Even if it's a scrapbook of anime stills or a crappy fanfiction, making ANYTHING is better than using only social media for entertainment

Might as well play Oblivon for the fifth time

Yeah but it’s Lemmy so you can check at least 6 apps that are all Lemmy

Hey, shouldn't you really do laundry? Sort your shit into darks and lights and start with whichever is smaller to get the ball rolling.

Have have too many videogames and a lot of overdue art projects. This never happens to me.

This is a mystery to me. Since being a child I always had so mane projects to do and so little time. And now as an adult with children the whole thing is even a lot worse worse.
Last time I was bored must be decades ago.

Drink

Or take 'shrooms

Exercise and/or do a hobby

Nap time

See if there is some place in your community that could use a volunteer. Research studies consistently find that volunteering with charities makes people feel happier. There's plenty of needs out there. One that might not be well known are Weed Warrior groups that work on removing invasive plants to make more room for natives. I find that kind of work really satisfying because there's an obvious visual of progress and success.