Webflow does not currently support uploading video to the CDN (except for background video) so you would have to use a supported source. That source would need to support you restricting access, not webflow.
You could certainly build a front end site here, but you realistically need another specific solution for a video paywall.
Hey I’d also recommend checking out MemberSpace. It allows you to truly secure your video content and has a lot of features for payments and dripping out content