Changing a light switch

Hello

FYI I have very little knowledge of our house wiring circuitry so apologies if I make any mistakes.

I’m trying to replace a light switch in our 6 year old house. I’ve done nearly every other switch no problems buying the replacement switch required and matching the wiring however I’m struggling with this last one.

It’s part of a three landing set up so understand that it is the intermediate for the loop of one light and three switches however it is a double switch with only one…

Changing a light switch