Welcome! I loved living on my own because it made me fully in charge of the foods and choices I made. I consciously didn't purchase or keep unhealthy foods in the house, which meant I needed to actively drive to the store to get something if I wanted it. That also meant I had plenty of time to talk myself out of it!
My favorite tip is to cook a full dish and portion it into the number of portions it provides. Freeze the extra portions and you have your own frozen meals that are unprocessed, cheaper, and catered to your dietary needs and tastes. That way when you're too tired to cook, you still have a healthy meal readily available that is in the correct portion size and no seconds (unless you want to defrost an entire second entree!).
You'll find a lot of tips and tricks here