I know that there are regional and family recipes. Where the key is - here in our region and our family - this is the proportion. Pre-made for you as life gets busy.
But basically - Garam Masala means the “hot/warm spices.” Or more accurately - warming spices.
Cumin
Coriander
Black Pepper
Cinnamon
Cardamom
Cloves
(Sometimes also fennel, nutmeg and/or mace, dried chili, black mustard, and/or a few others)
The “sometimes also” is important - that gives you familial and regional variations. The core items is also important as you can adjust proportions between them to ensure your dish is more Punjab or more Bihar.
You can also just decide to dry roast and use/oil bloom whatever among the subset of the above spices you want directly for the balance you desire for your dish.
Just a PSA for all the peeps stressing about this blend.
PS. Edited to add - this should be “warming spices” not hot, because most folks associate heat with scoville heat, and don’t realize spice is not always about the chili. These are warming spices, not heat as the western language thinks about flavor.