My first suggestion if you have a Raspberry Pi Zero 2w or better is to install Klipper. If that isn't a route to go down for you then Myers firmware was really good (not sure if it's still around since I went to Klipper).

I've printed so many miss for mine, spool holder moves to the side, filament guides, different spool holders with bearings, new hot end fan assemblies ,small tool holder that slides into the v slots. Covers for the V slots.

It's a great machine to learn and tinker on, some people don't like that but I really enjoyed it.

I've since switched to direct drive instead of the Bowden tube and added another Z rod and stepper. I have a microswiss all metal hotend which has been fantastic and I have put Noctua fans for the heat break. Also upgrade the Bowden tube to the Capricorn type, it is much better.

A magnetic build plate from Biqu was another good addition.

Almost forgot, I printed risers for the feet out if TPU and that seems to help, I probably would have tried the ones that the squash balls go into but these work fine. In order to print TPU with the Bowden tube you need to print slow.

Also keep an eye on the plastic handle on the filament extruder, they are known to be weak and crack, a good aluminum dual gear is a good low cost investment.

Search on Thingiverse and Printables for mods for the Ender 3 and you will be overwhelmed with your options.

Patience is a virtue, and remember there are no stupid questions and a huge community of people willing to help.

If there is anything else I can do to help, don't hesitate to ask.