What version of macOS were you on at this point in time? If you were past macOS 14 then they changed how to open Apps that it doesn't consider signed properly
It's now Double click on (SUBTERBALDI).
When the pop-up warning appears saying Apple cannot verify the app, click Done.
Then goto Settings ==> Privacy & Security and then scroll down to the bottom of Privacy & Security.
You should see a text block stating the app was blocked. Click the Open Anyway button right next to it.
It should be somewhat straight forward from this point onwards, your Mac will ask for your password several times during this.
If your account isn't an administrator then you'll need to contact your administrator to put their password in