To add to all the other answers about what to use and whatnot: try a few distros and desktops out by putting them on a flash drive and booting from the flash drive (this is the same process for typical installations)

Distro, or who the linux based OS is built, updated, and distributed by, mostly matters long term, but something that will keep working and be stable (in the colloquial sense, not technical sense like for servers), and that has a friendly and welcoming community, are definitely things to look for. Mint and ubuntu both have stellar reputations in both of these regards, though many folks (including me) have issues with decisions being made by the ubuntu folks these days. Fedora is pretty stable but has less of a big community with support for new people, and manjaro has a lot of newer users and is built around serving newer linux users, but the project is sometimes run in an awkward way that can cause issues if you're not choosing to manage your packages with intentionality (thats what I hear anyway). Debian is rock solid, and I dont know much about the community, but the versions of software available in the repos may be old unless you're installing a flatpak

Keep in mind, not all distros will support every desktop, so you may find your chosen desktop isnt available on the distro you find most interesting. You can theoretically install whatever desktop on whatever distro, but as a new user I dont reccomend doing this.

Definitely try out a few different desktops. "Desktop environments" are bundles of software that make up the desktop graphical user interface, and will make a big difference in the look and feel, and general user experience that you have on linux. There are a bunch of options- the two biggest projects are GNOME and Kde plasma. Gnome has a reputation for being more mac-like out of the box and has very specific workflows and usage patterns, and kde, more windows like and flexible to what the user wants. But both are customizable. Kde has lots of built in settings and options, gnome offers very few, but supports user made extensions that change the desktops look and behavior. Give both a try and try out the customizations for each (play with kde settings, see if you can make it more what you want. Install some gnome extensions, see what the options look like). Cinnamon is another desktop thats very windows-like but has a great user experience. Xfce is a well run project but predominantly aimed at being lightweight so it runs well on older hardware, you're less likely to be in its target demographic