Video editing question: pausing the video

[Sound asleep]

Let's say I have a video in reaper, and I want to add voice over to it, and then at one point I want the video to sort of pause, while the audio continues over it, and then resume again afterwards. I'm think I could just copy paste a single frame however many times is necessary, but I'm not sure about how to isolate a frame, and to easily copy paste it so as not to leave any empty spaces.

Can I set my grid to video frames? I would guess not? since I dont' think I told my reaper project how many frames per second I want, or anything like that.

Also, how good is the video rendering in reaper? I could do all of that in after effects, but I want to be able to adjust both the video and the audio at once.

Right now what I'm doing is I'm going through all of the audio, and matching up the video loosely, without the pauses, and then I am planning on just rendering the audio, and then going into After Effects, and doing all the video in there, so it lines up how I want with the audio I rendered, which kind of means I'm doing the video twice almost. which sucks.

Any ideas how I should go about this?