Removing Air Intake Grill

If it’s sim to Gen 3 there are small plastic pieces at the two ends that have to come off first. If you pop the hood you can remove their fasteners (they have a head you push down to release) then you need to simultaneously pry up on the lower end while pulling/sliding down. Then there’s more under-the-hood clips along the the main piece lower edge: all need to be compressed and pushed/pulled out. Then it needs to be pulled towards you and down, to get the underside tangs to release.

Removal (of Gen 3) is shown here, hopefully similar enough to help, in video #13:

Nutz About Bolts Prius Maintenance Videos | PriusChat

hopefully considering you’re Gen 4 (and my flakey recall) I’m not completely blowing smoke.

 

Welcome Mike,
I couldn't find a video specific to the gen4 Prius, but the procedures are very similar.

https://www.youtube.com/results?search_query=prius+cowl+removal+

I've only gotten as far as removing the access panel for the brake fluid reservoir and use a shop vac.and brush to clean-up the leaves.

Hope this helps...