Ha. No worries. List of distributions...

• Pop!_os Arch derivative. Popular. Quite easy
• Debian One of the first distributions. Medium to hard difficulty
• Ubuntu Very easy, but they are a bit corporate. Usually considered a good beginners distro
• Slackware (beginners guide). One of the first distortion. Can be considered hard mode :)
• Manjaro Arch derivative. Easy to medium
• Arch Arch (not a) derivative. Hard mode
• Redhat Enterprise mode

I would try them out as either live usb tests or in virtual box first to see what tickles your fancy. In the mid to late 90's I was using slack and Debian. Debian is generally used as a base in docker images for its stability, so getting to know that to get into herding containers can be a good thing.

Many others out there, that's just a small list off the top of my head.

• List of distros

• 'nother list

• distrowatch used to be my go to when hunting fun distros.

• Have fun!

• Break shit!

• Learn how to fix it (almost every catastrophe is recoverable)