trying to fit gallery view of 15 participants in webinar along side sharing PP slides presentation

Hello,

I have a laptop and a 27inch second monitor. I use my laptop to run zoom for webinars of around 15 participants.
I use my second monitor to share slides but when I do it the gallery view overlaps the slides.
I have tried to go to 'My Screen'  at top of my screen 1and play around and yes I can have it in side by side with me next to it, but the slides do not move. I end up going back to 'meeting' at the top of my screen and just have to move my gallery view off the screen if I need to see all of the slide content.
Is there a way I can see the full gallery view of my participants and reduce the size of the slide area so that i can still all of the slides and have them still moving through the presentation?

Hope you can help.