Just a quick comment.
Am I wrong? TLDR. A "12V" LED display would have internal current limiting resistors. Have we been given the essential weblink where we can check how it is configured and thus, how to use it? Otherwise, it's just pi$$ing in the wind.
To use a digital multimeter to measure current, you either connect your test leads to the left hand and centre jacks on the meter and use the "10A" range, or you connect to the right and centre jacks and use any other current range (in this case, the mA).
