There was a thread on reddit asking dentists questions and what stood out to me was unanimous agreement in multiple separate convos of dentist redditors that electric toothbrushes work better than manual. The theme every time was: Use electric. Use very light pressure (don't even open your mouth too wide because your cheeks add pressure). Spend a good amount of time on each tooth --to the point they recommend brushes with built-in timers to keep you on the clock.

As for flossing: All I know is that before I started flossing, I was accumulating measurable gum damage. After I started, it healed. Now when I slack off, I get sore spots. When I start again, they heal. And, when I'm flossing I find it incredible how much gunk I pull out of my gums even right after a through brushing. It's gross. But, far more gross would be just leaving it there to rot.