Both Mullvad Browser and Tor Browser use it, so it probably is safe to use. However, as the Arkenfox project states, NoScript is redundant with uBlock Origin. What exactly do you find confusing about blocking scripts with it? If you haven’t done so, you should read the documentation related to it. Also, The Hated One has done a Youtube video about this a few years ago. It is a bit outdated, but it might make you understand the concept better.