Zoom toggling options in macOS

Low Vision Accessibility on Apple Products

Can I map a button on a third-party mouse to toggle zoom on and off?
I’m thinking of getting my first iMac this summer after using iPhones and iPads for years. I’m severely visually impaired, but zoom and VoiceOver features in iOS have proven to be very hopeful. I’m hoping that the accessibility features of macOS will be equally useful.
I’ve been watching YouTube tutorials to figure out how accessibility features work in macOS. There seem to be some options when it comes to choosing keyboard shortcuts to activate these features. But honestly I’d prefer using my Logitech mouse and one of its extra buttons to toggle zoom. Is that even an option?

I was also wondering if I could use the magic trackpad and my Logitech mouse at the same time. I love the simplicity of zoom in iOS, where I just double tap with three fingers to zoom in and out and pan around. Do similar gestures work with the magic trackpad in macOS?

Thanks in advance for any help and advice you guys can give me.