Another 'is this ok' one, I'm afraid. I've only been in tier 4 since midnight so still learning the ropes!
Is it ok to use public transport to get to/from shops for food shopping, or to get to a local wooded area for a walk? Shops would be about 2 or 3 stops on light railway (so about five minutes), for exercise it would be about 15-20 minutes. I have mobility issues and have a concessionary pass if that makes a difference - carrying lots of shopping home almost did me in in the first lockdown. No access to a car, no local help and no delivery slots for weeks around here. I would always go at quiet times, too. Shopping would be twice a week, the exercise thing once in a blue moon really.