- Download Mint
- Download VirtualBox
- Setup a Mint VM
- Get used to it (this is a long step, you're free to try other distros, take your time)
- Download Rufus, install a Linux ISO of your choice to the USB
- Shrink Windows' partition
- Turn off Secure Boot and RAID in your BIOS (steps vary by laptop/motherboard manufacterer)
- Boot your USB (try booting it in EFI mode instead of BIOS mode first, if you can)
- Follow the install instructions to install it alongside Windows
I gave what I think are the easiest and most beginner friendly instructions (Mint over Debian, Endeavour, Fedora or Ubuntu for example). Not all are the best suggestions (I suggested VirtualBox over QEMU and Rufus over Ventoy), I recommended you to go with your own preferences if you have any
If you run into any problems, this Lemmy community, the Ubuntu SO (also for non-Ubuntu questions, everyone is there) and the Mint Forums for Mint related questions are always there for you, don't be afraid to ask and "don't ask to ask" ;-)
Good luck!