as mentioned in another comment, yt-dlp works great. there are graphical versions of it that i haven't used. i use it on linux but it has a windows version too. full discolosure, i haven't used it to download videos in awhile, i mostly use it for music, so this info might be outdated.

the basic premise is you find the video you want to download, copy the URL, paste it into the yt-dlp program and it downloads the video.

there are a ridiculous amount of options however, the github might seem intimidating if you aren't a programmer or very tech savvy. there are plenty of better written tutorials online. once you get it to work, it's easy after that.

if you are in the U.S. try pornhub, xvideos, xnxx, xhamster or tblop. the ID requirements vary from state to state, so if the first 4 don't work, keep trying off tblop until one is found. there's also streaming archivers like archivebate and peachterbate.

one last thought, if you don't have ublock origin, get it. if you have it, make sure to go into the options and check the all the 'annoyances' boxes. i think it removes the 'we need a picture of your id' messages on a few sites.