Solved by u/NoraJolyne:

have both the drill and fuel in your hotbar. put the drill in your off-hand (by pressing F while selected, for example), then switch to your fuel and press Q to drop it

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I know this is an extension mod, but I honestly don't know of any other place to ask.

I got the Brass Portable Drill from the Create Stuff Additions and for the life of me I cant fuel it up.

The only guide i got is on the curse forge page under another category is this:

fuel (to recharge, put it in the second hand then drop the fuel like charcoal, blaze sticks or wood)

I tried this countless times, tried multiple fuel types, many slots shuffling, even using fuel and other methods. so I have no idea what it wants from me, there are no videos on this because it looks like the fueling method updated recently.