Do you have a link to what you purchased? That can help give a specific answer to your equipment.

Your buttons have separate pins for the button action (micro switch) and the LED. This can be good because it means you can power the LED separate from the button functionality.

I'm going to guess you have something like this:

0_1524260873912_4ccfb34c-a7a0-407d-ad73-1d3e0ebdcab1-image.png

The two pins on the top are the switch and you can tell this because they are connected to the little grey box (which is the switch itself) The yellow is positive and the black is ground.

The bottom two are the LED and similarly you can tell because they are not connected to the switch (little box). The red is positive and the black ground. In this image the ground is daisy chained, which is fine but you can ground the led separately if you want to.

Now for the Wire connectors.
It sounds like they sent you button connectors (two wires, two pins). This can work if you are going to wire up the LED power separately, but they should have sent you 3 pin connectors that would connect to the 3 pin led button slot like this;

0_1524261463917_43920c32-d487-4097-8947-dfd2a0e68239-image.png

I'm explaining using a lot of presumptions here so I will wait and see what you have before going any further.

As for 12 volt led buttons. That is a bit odd and over powered. easiest way to test is to wire one up to a 5 volt source and see how bright it is. If it works well enough for you GREAT. If not then ramp it up to a 12 volt and see what you get. Once that is answered you can look into set ups that will work (IE external 12 volt source) or replace them with 5 volt led buttons.