I'd like to see some kind of way to lock the system for older folks. I'm tired of troubleshooting my dad's computer. He doesn't even do so much as adding bookma

I'd like to see some kind of way to lock the system for older folks. I'm tired of troubleshooting my dad's computer. He doesn't even do so much as adding bookmarks, his machine exclusively browses the web. I'd like to get everything he needs installed and lock out modifications. Needs cookies obviously, but not much else. Somehow he manages to have video player issues in every single browser that I can't figure out. He has to watch youtube in chrome, live streams in firefox, etc. It's really dumb. Buying him a chromecast improved it some, though, by avoiding it.