Congratulations, man! I'm grateful you joined the challenge and happy you started to run. As for running, I will not try to get better times as of right now. I won't focus my efforts towards getting faster, because this will happen naturally, once your aerobic fitness will improve.

If you can get a HR belt, I will insist on planning your training around that HR belt. I will run in such a way that I will never go over my MAF heart rate (Maximum Aerobic Fitness). You can calculate your MAF using this formula:

180 - your age. So if you're 40, your maximum HR rate should be 140. Even if you walk in the beginning. Believe me, it works.

Keep it up and do post updates about your trainings.