It's not your computer, per se, that stores details of the websites that you've visited but your browser. So you need to clear your browser's history. The instructions for doing so vary between different browsers but this link covers all of the main ones:
https://www.howtogeek.com/304218/how-to-clear-your-history-in-any-browser/
If you don't like having your browser store a record of all the websites you've visited, it's very easy to disable that feature altogether. (I always disable it). If you need instructions, please tell us which browser you use.