How to create variables in Google Tag Manager on click?

Question

Google

Friends, I'm sorry if this is a stupid question, but this is the first time I've encountered Google Tag Manager, I've read the help, googled it, I'm stupid .... In general, there are a lot of DIV containers with a buy button. By pressing this button, you need to pull out several variables from this container. The trigger hangs on the same buy button... , there is no access to editing the page code, so I would transfer everything at the data level... Through custom JS? hang a listener on buttons, then return a bunch of variables or an array on click and substitute them in the tag?