1: Natively. Plug in your iPod touch, and open a finder window. You should see the iPod touch on the left hand side under 'locations'. When you click it, you'll be greeted with the familiar sync screen from iTunes. You can sync podcasts like you always did by clicking the podcasts tab.
2: Get retroactive from github which will install an older version of iTunes natively under Big Sur. Works great! Then you can sync your podcasts using iTunes. Unless you have a reason to use an older version, I'd use iTunes 12 for compatibility and reliability.
You can also log into your iCloud account on the iPod touch and set it to sync them that way through Settings, so your playback history and subscriptions are automatically synced.
You can also log into your iCloud account on the iPod touch and set it to sync them that way through Settings, so your playback history and subscriptions are automatically synced.