help please

Powdery mildew. Use 1tea spoon of arm and hammer 🔨 whit a gallon of water spray generously on the leaves

Kinda looks like powdery mildew to me.

It's powder mildew, oidium! It's relative late stage, but don't worry you can fix It. It lives in acid habitat, like the leaves (5.5pH), so to kill It you have to mix 1gr baking soda/L water, to have a pH of 8. Spray it once a day for 3 days after sunset, and do a defoliation and cut off pop corn buds so that it passes air better (yes to indoor and outdoor plants), it should work. You can spray the plant with just water on the fourth day to remove the bicarbonate residue. Next week repeat if necessary, don't spray last 14 days of flowering(you need more than 14 days), Its not harmful anyway . Put the outdoor plant at sud if you can, and where she receive more wind.

That, my friend, is powdery mildew. I've been fighting it for the past few weeks due to how wet it has been here in western NY. Get some fungicide and spray the plants down. Dr. Zymes works all the way up tuntil harvest and I fully recommend it. Good luck.