To get rid of moz browser extension go to your browser extensions settings and disable or delete it fully from your browser extension menu.
Then after deleting the moz browser extension you will need to restart the browser and clear it's cache.
The exact way to go to the settings on your browser will depend on the browser you have.
But you open your browser's extensions or add ons menu such as Google Chrome's three dot menu or Firefox's hamburger menu.
Then look for the MozBar extension.
Once you find the MozBar extension you can select the option to "remove" or uninstall" the Mozbar browser extension.
Once it's been uninstalled you then close your browser out and then restart the browser and clear the browser cache and cookies to fully remove the moz browser extension.