If you want to check out some linux distributions, I would suggest you use Ventoy. You can then copy the ISO's to your USB drive and boot from them without having to reformat your usb drive all the time. It's a really cool tool and I can highly recommend it. I always carry ventoy with me for work with rescue disks, clonezilla, etc.

Personally I would recommend either Ubuntu or Kubuntu (Ubuntu with KDE - it's what I use). It's a one of the most popular distributions and well-documented and supported.

If you want to have a look at what's available, check out https://distrowatch.com/

Edit: If you're not ready to install on your own hardware, try playing around with Virtual Machines - like Virtualbox.