Newbie trying to use cmd plug trackpad scroll top and down to zoom in and out

Hi everyone

I can't believe I have just come across this great tool.

I use Affinity Designer and Figma, Figma uses cmd and a two finger slide up and down to zoom in and out, affinity designer uses option and a two finger slide up and down to zoom in and out.

This gets confusing and I wanted to change Affinity Designer to match Figma.

I can't work out how to do it. I selected affinity designer so it only works on this. I then selected two finger slide up and ticked cmd but now I don't know what to do from here.

I've been searching for ages but as I am new, I think I am searching for the wrong commands.