You will find this in your browser menu or settings. It depends on which browser you are using. If you can't find an option to clear cache and delete cookies on your specific browser, you can search the topic on Google with the browser name you are using.
However, here is how you can clear cache, delete cookies on some of the most popular browsers:
1. Google Chrome: https://support.google.com/accounts/answer/32050
2. Mozilla Firefox: https://support.mozilla.org/en-US/kb/delete-browsing-search-download-history-firefox#w_how-do-i-clear-my-history
3. Opera: https://help.opera.com/en/how-to-clear-browser-cache-history-cookies/
4. Microsoft Edge: https://support.microsoft.com/en-us/help/4027947/windows-delete-cookies