How do you take out the black burnt spots out of stainless steel?

Have you tried Bartenders Friend with a microfiber cloth? Won’t scratch, but go with the grain of the steel. First I think I’d heat a damp rag in the microwave to warm, put it on the spots and pour a bit of vinegar on them and let it soak. Wipe off vinegar, again following the grain.

I usually soak it real well and use an abrasive pad on it, if that doesn't do it, I get out the Brillo pads. Best solution is to not cook on such high heat, and use the right oil that won't burn for what your cooking.

try making a mixture of baking soda and cream of tarter

Another option would be to call the manufacturer for their recommendations. Wishing you the best.

Here's a tutorial for you! https://www.apartmenttherapy.com/how-to-clean-burnt-pots-scorched-pans-140547

I use a very fine sand paper to remove the burn. 800 grit

https://www.hometalk.com/diy/clean/house/easy-way-to-clean-a-burnt-pot-or-pan-17630473?r=1

https://www.hometalk.com/diy/clean/house/cleaning-tips-burnt-pots-pants-5383049?r=1