Wow, 90 watts to start? And with 12mg juice? I would back off of that a bit. Assuming you got the TFV-8 Baby Beast in the kit, try the .4 ohm dual coil at about 30 watts to start, or even the .6 ohm dual at about 20 watts. The .6 is rated up to 50 watts and recommended 30-40, while the .4 is rated to 80 watts and recommended 55-65. If you find the vape is too weak to please you in that range, you can move up to a quad or octuple coil. Seriously, 50 watts, not to mention 80, is some pretty serious power on a vape coil; it would be unusual for a beginner to move directly there and like it enough to stick with it and quit smoking. If I tried to vape at 90 watts, I'd get a burnt taste too, but it would be my throat lining, not the coil
And no matter where you go, 12mg juice is almost certainly too much nic for direct lung-- inhaling directly into the lungs, not taking a mouthful of vapor and then inhaling it-- subohm hits. Three to 6mg is much more normal in that power range. Everyone is different, of course. Maybe you're a 4PAD chain-smoker trying to quit and you need that much nic. But I was a 2PAD smoker for decades and if I tried 12mg juice at my feeble little .5 ohm coils and 40 watts, I'd have a headache after 3 hits and be nauseous and puking after 12 from the nic overdose. The juice in question need not be wasted, if you decide 12 is too much. Simply buy a bottle of 0mg in the same flavor and mix equal volumes for 6mg, or 2:1 for 3mg.
Not trying to bust your chops here, dude, or tell you what to do. Please yourself. But I am trying to get you started well. Welcome to the board.