Depends on how you want them to show up. If you just want them to show in your main feed, then upload the video to nostr.build and copy/paste to any client you prefer. Some clients like Amethyst or Coracle will let you upload to nostr.build directly through their interface.

The above methods don't let you title your video or add a description or anything, though. If you want that, you will need to use Flare.pub or perhaps zap.stream. I haven't tried their video upload feature, yet. Then you can always share the video in your main feed from there.