I have only very briefly used Brave, so I can't give you a full answer here. However, since Brave is based on Chromium (the same framework that Chrome is based on), many Chrome extensions will also be compatible with Brave, and it should be as simple as installing them from the Chrome Web Store. Have a look here for some more information: https://support.brave.com/hc/en-us/articles/360017909112-How-can-I-add-extensions-to-Brave