Maybe it would help to start at the beginning:
Linux is an operating system for your computer like Windows, only different. There are as many different reasons for preferring one over the other as there are people - it is not always about performance. The choice of Linux over Windows could be about freedom of choice or many other motives.
Linux comes in "distros". Each distro is its own operating system like Windows. The people behind a distro decide what they want to package together for their distro. As a result, different Linux distros can look very different from each other when you use them - they are essentially different operating systems under the "Linux" name.
The look and feel of your Linux distro happens in its "desktop environment". Linux distros choose a default desktop environment for you. A few distros come with a choice of alternative desktop environments. Ubuntu Linux uses the "GNOME" desktop environment, but offers alternatives like Cinnamon and quite a few others. (You can change your desktop environment later, but it is better for beginners to stay with the default at first.)
"Linux Mint" is the brand name of that distro. The "Mint" does not mean anything even though the default desktop environment is called "Cinnamon".
The problem with Linux is choice. There are many distros to choose from. Each distro is an assembly of different components that have much in common, but the look and feel of the user experience can be quite different between them. Because everything is under your control, you can replace, modify, or change any part of your Linux installation, but the number of options and choices can feel overwhelming.
If you are getting started with Linux Mint, it will run perfectly fine with 4 Gbytes of RAM. My current Linux desktop is Linux Mint Cinnamon, running in 4 Gbytes of RAM. As long as you are not doing video editing or something that needs a lot of RAM (not likely for you), then give Linux Mint Cinnamon a try.
My advice: Take one baby step at a time. Try stuff out until it feels more comfortable, then keep going.