Updating from Sierra to a more recent osx

I just put a new SSD in my old macbook pro late 2012. Now I know these aren't compatible with Big Sur, but they're at least compatible with High Sierra or Mojave. But somehow, I cannot update it past Sierra, there's nothing showing in the app store, I've restarted my computer many times and nothing happens. A lot of the apps I use aren't compatible with Sierra and require a newer version, how so I update to High Sierra or higher?