What have you attempted so far? I’m thinking here of things like adjusting Motion Detection Sensitivity for the camera and hitting the on the upper-right corner of the app’s Home screen to temporarily disable notifications for the times you expect activity in the garage (this allows you to set a custom “off” period for notifications, and then they’ll turn on again when that time is up). One potential problem with using the bell is that it’s a global on/off setting, so it’ll affect all your cameras if you have more than the one Cam v4. You could also create Shortcut Automations to enable/disable the notifications for that camera and set these as Favorites for easy access, but then you have to remember to turn the notifications back on again at some point (or create a Schedule Automation to do that for you).
Then there’s the new NBD Filter, but that might be overkill for what you’re attempting to do with a single camera.