content is orders of magnitude less than youtube, so you may not find what you're looking for.
Instance search is highly limited by federation. To search all of PeerTube you want to use https://sepiasearch.org/
no great android apps yet, thorium, fedilab, newpipe, and grayjay are the best options I've found so far, all have failings. Framasoft has an official app on next years roadmap. Podcast apps have various levels of support when using a channel's RSS feed.