Will there be some sort of OS running on this VPS like Ubuntu, Debian etc.? The folder my Lemmy instance is stored in is 117 MB big. I have 1 user and follow 23 communities.

I use Ansible in my homelab for my Windows server since I already had it setup for some Linux hosts. https://www.ansible.com/for/windows

I installed my own Lemmy instance today. I did use this video to get a more visual explanation of how it works: https://youtu.be/6lQFZvCCe7U. Hopefully this helps.