Adding a shape into a video in adobe premiere elements(small rectangle)

So I downloaded adobe premiere elements 2026 and opted for the 7 day free trial because I need it for a small comedy project . I haven’t edited in about 15 years since high school.

I want to add a small black rectangle over someone’s mouth in one of the videos to create the effect of censoring because of cursing. I’ll also of course add the well known bleeping sound effect.

Im having a lot of trouble adding the black rectangle though. Tried adding it in the text box but no luck. Tried adding an image of a black rectangle and scaling down the size but it just replaces whatever part of the video I overlay it on.

I know this is a super basic inquiry but im super basic at editing. Any help would be appreciated.