Agree that bagging watch is important step. Time - pace not important at this juncture Just ease into your comfort level by accumulating a few more miles each week. Not fast Not too long. Will take a while fir breathing and heart rate to figure out what's going on but they will adapt. After a month or so - some pickups or strikers - short / like a minute or so - are in order avoid injuries that occur with too much too soon
I came back 2 years ago after a really long break and being patient and taking it overly easy going back in is key. You definitely don't want to be looking at the watch much, just focus on building up that base slowly. Doing too much too quickly can burn you out, lead to frustration and increase chance of injury. I didn't focus on time or racing for months after starting back up. I'd focus on heart rate instead of pace....140-150 which is where you'll be improving your aerobic capacity.
3-3 (strides in/out) is a typical breathing rhythm or 2-2 if you're working harder. But if focusing too much there is messing you up, just try to run "relaxed" and have your heart rate be a gauge and your breathing should more naturally fall into place.
For eating, I just try to eat a wide variety (think food pyramid, lots of colors) and stay away from obvious junk....I agree with the other commenter unless you're doing super long distances, just eating reasonable works. After hard or longer runs, you should always try to have some protein and some light carbs within 30 minutes for replenishing muscles.
What your heart rate range during training larger depends on your age. First you need to calculate your max heart rate which is 220-your age. On most of your runs you should try and be at 70-80% of your max heart rate. Tempo and workouts would be in that 80-90% max heart rate range. Hope this helps
