"Most people are wrong about most things."
People give advice that is out of date, just plain wrong, irrelevant, self-serving, or otherwise generally useless. The key is to just ignore it and do whatever you want.
Over time you'll figure out what works and what doesn't. And in 30+ years of living, the only thing I've figured out that works is to ignore all the advice I receive.
I don't really have a set way I cut out the noise - but I definitely try to in as many ways as I can. It helps me to look at it as a fear of loss/fear of missing things and when I make note of that fear - I can ignore the noise more easily.
Start with getting 6-8 hours of sleep a night, consistently. Go to bed and wake up at the same time every day. Perform physical exercise for 45min - 1hr a day. That alone will allow you to manage your time significantly better.
A consistent wake up time anchors your sleep schedule, and prevents you from accruing a sleep debt. Most sleep debts gradually sneak up, and can be hard to diagnose.