if by modloader you mean something like forge, yes, I made sure in all my trial runs that I had the correct loader and version of. I think it might be an issue with how I’m uploading the mods to the server itself, but I don’t know what I’m doing wrong
The Jar also needs to be Autoselect
Be sure that you’re uploading the mod jars to the mods folder, and not the CurseForge manifest zip (as that’s only for clients, not servers)
Then check the logs to see if the mods are loading correctly.
Forge specifically has a forge mods command that you could run in the console after the server has started.