Very simple to test for a draw, especially with a multimeter. You can pull the negative battery cable, hook the multimeter between the cable and the battery and measure the draw in current mode.
https://www.optimabatteries.com/en-us/experience/2010/12/what-normal-parasitic-drawThere is a video link at the end of the article on how to do it
Tell me which model multimeter you have and I will tell you how to use it.
Don't forget to close the door and if you have a hood light pull the bulb with the hood up. Basically, you do not want to turn anything on while doing this test or you will end up chasing your tail.
