Something that doesn’t take a lot of mental processing, but takes some time, so it’s still rewarding, and is very relaxing, and gives you a product you can be proud of.

Make a small aquascape. A small cheap tank so it doesn’t break the bank. The difference between an aquascape and a fish tank is that it’s more about the scenery and plants than fish, much less maintenance and lesser learning curve between species, just like how most people can have a garden in front of their house with little issues. usually just a few colorful fish or shrimp to interact and create variation in the visual display.

Like a bonzai tree, you’ll just trim and remove some plants as they slowly grow out of shape. Occasionally take some water out and replace it with new water. Occasionally add some nutrients. Really, you usually don’t have to do anything to it for a week at a time, but also you can spend time on it every day if you’re bored to improve and maintain its cleanliness and beauty.

Check out this piece of living art, this is called an Iwagumi style, but there’s all kinds like Dutch (basically a dense underwater flowerbed), or nature scape (mimicking natural land features like forests or mountains).

Many people find peace simply watching their creation. But it’s a world of easy-to-process information and learning that can be as complicated or simple as you want to make it.

Clearly, I’m biased. Lol just a suggestion.