Coding help! BOGO

[leoking]

 

https://luckyfours.com/products/caspian
has this section I would like a exact replicate, the switch watch I’d prefer to be called switch item and to let the customers switch any product from that same collection only. Let me know if this is possible thank you.

[leoking]

I tried plenty of methods unfortunately even apps nothing got close, so I’m really just looking for coding steps on how to do it