+1 this, as it also helps to sleep better and that makes a huge difference.
It's important to be consistent because it takes some time to start noticing the benefits.
Also, create a bed routine and stick to it. For example, taking a hot shower, brushing teeth and then going to bed right after help to slow down a racing mind.
Reading a book before bed as well, I'm always impressed how much I can read and how slow the time goes by and I'm already sleepy.
I can confirm that exercise and fresh air helps. As for sleep - do not oversleep. I had enough good sleep already, so sleeping more than 8h is counterproductive. If you feel sleepy, absolutely positively commit to two full days of doing nothing (no phone, no "doing chores" or tidying your home) and sleep whenever you feel like it. After this, try to create a routine, where you get 8h of sleep, but don't snooze. When alarm rings, just get up, or at least sit for max 5 min, don't lay on bed.
"Reading a book before bed as well" - doesn't help everyone, I get too excited with story and have trouble with stopping reading when the time comes.
You may struggle for time to exercise from the sound of it, but even a little bit helps.