New golfer looking for simple swing staples and drills that actually helped you

I’m a relatively new golfer. I watch a lot of golf on YouTube and follow tour events, but I’ve never had a lesson and don’t play super often.

I usually shoot around 90–105. I’ve never broken 85 but also never go above 110, so I kind of know how to swing but clearly still have a lot to improve.

I’m looking for simple swing staples that helped you. Things like “turn shoulders not arms,” “don’t start the swing with your wrists,” etc.

Also any drills that genuinely helped your swing.

Every video seems to contradict the last one, so I’d love to hear what actually worked for you.