Ah, ok. That's a different mods folder.
Open up a file explorer window, and click in the navigation bar (where it has a list of folders, with the last one being the one you're currently in) and type "%appdata%" (with the percent signs before and after). If that doesn't work, you can manually go to C:\Users\[your username]\AppData . This folder is hidden by default, so if you're browsing to get there, you might need to enable "view hidden files and folders" in Windows.
Within that you should find the Roaming\Strive for Power 2\ folder. It probably already has a "mods" folder under there, but if it doesn't, you can create one.