The most reliable way is to use paid hosting. Two that are integrated into Nostr are Nostr.build and Satellite.earth CDN. Both paid in sats. Satellite is a bit more cost effective as you only pay for the storage you actually use. With Nostr.build you pay for bulk storage (along with some other features) whether you use all of that storage or not. Primal seems to allow uploads for smaller video sizes but I’m not sure what that size limit is.