A Linux distribution is a similar concept to a phone’s app store. It allows you to download software that’s pre-vetted. This reduces the chance that it’s malware and allows the different dependencies to work together to reduce redundancy. However, you MAY optionally get software OUTSIDE of the package manager and directly from the software’s developer, through universal systems such as Flatpak, AppImage, or Snaps.
If you get software from OUTSIDE the package manager, then you’ll have double dependencies which takes up space and causes some minor delay in starting up the program. Many in the Linux community argue and debate over if the delay, space, and security issues matter, or if it’s more important to have software that works across distributions and is released faster. The delay on Snaps is worse than others, leading SOME to criticize Ubuntu which heavily uses them. This is why Mint is a fork of Ubuntu but WITHOUT Snaps. Others point out that without universal package managers, it can take YEARS for new software to make it to distributions with slower release cycles such as Ubuntu and Mint.
A Linux distribution is NOT the way Linux LOOKS. That’s the desktop environment! So if you like a distro’s software, you can swap it for any other desktop environment than the default. For example Linux Mint’s “Cinnamon flavor” look, could be put on Debian or anything else! At the end of the day, distros DON’T matter that much and anything is better than Windows… even snaps =)