YouTube's Autoplay feature automatically starts playing a new video after you finish watching the current video. Autoplay videos are related to your viewing history and help you discover more content. Here's how to turn off autoplay if you don't want new videos to start playing automatically.
How to Turn Off Autoplay on YouTube (2021)
To disable autoplay on the desktop version of YouTube, follow these instructions.
If you're not already signed in to your Google Account, select the blue Sign in link in the upper right corner to enter your credentials and sign in.
Search or select a video to go to the page and start watching. You don't have to watch the whole thing and you can select the pause button to pause it.