I see Input Mono is mentioned, but I actually really like using Input Sans, also from Font Bureau. It's a proportional coding font. I feel like I'm living in the future.
You can get it here: https://input.fontbureau.com
And amazingly, you can personalize your font on download, such as choosing dotted vs slashed zeroes.
Not free, but free for personal, non-commercial use. (Check the terms)
For ~6 months I used Comic Sans as my single font system-wide - like, for everything. Everywhere in the system UI, code, even on webpages (Firefox lets you disable CSS font selectors). The only exception was the terminal, which got messed up with non-monospaced fonts.
It was actually surprisingly great. Then as soon as I got a 4k monitor Comic Sans started to look very ugly - if not for that, I would still be using it. These days I use GNU FreeFont (FreeSans) for the system & Firefox & IDEs, but I have started to do almost all programming through the terminal so I use Fira Code and [Liga]Hack for that.
So give Comic Sans a shot, you might end up liking it too :) (On Windows/macOS you probably won't be able to set it as your system font, but you could still use it in your IDE and on the web)
If you liked that, then you may get a kick out of Comic Code, a fixed width variation of Comic Sans designed for coding:
https://www.myfonts.com/fonts/tabular-type-foundry/comic-cod...
I've been using it for a few months and really enjoy it!