For old hardware try xubuntu, grab an iso of stable release like 22.04.

Debian based, has software store, xfce is not ram hungry, you can test from live usb before installing, xfce can look like any other os through panel configuration.

I started using it on an old machine, but still on it after I got a better pc. I do development in python, no issues at all. Happy to help if you have questions.