OP it sounds like you are fairly risk averse and have good reason to want to avoid covid more than most people. But also as though you may not understand how the virus manages to infect people and so are not accurately assessing relative risk.
A takeout coffee is low risk because the virus isn’t passed on in food and drink and even if the server had covid or had served a customer who had covid it would be very difficult to pass on enough of the virus via transfer on the cup for you to catch it. Similarly, catching it from cross contamination on your shopping is highly unlikely and wiping down shopping is not seen as necessary, especially if you refrain from touching your face and wash your hands after putting it away.
Being near people in an enclosed space, especially if they are exercising, shouting, singing, coughing or sneezing, is high risk because, if someone has it, a fair amount of the virus will go from their mouths into the air and pass with some force over a fair distance. If the air is still it will hang around rather than being dispersed and you are more likely to breath in enough of it to make you sick (hence why being outdoors and ventilation make a big difference). The closer you are to them the more likely you are breath in enough to make you sick. Masks seem to protect others by stopping some of the virus being expelled into the air making it less likely someone near a mask wearer will get enough of the virus to get sick so safe distance between mask wearers is less than between others. There may also be some protective benefits to the mask wearer, though I believe those benefits are less well established.
Even with underlying conditions, most people who catch covid seem to recover well. We have not yet been able to measure fully the incidence of long-term, non-fatal consequences, but we do know that most people recover fully.
How much risk you take is, ultimately, up to you. I don’t want to minimize the risk of infecting someone with underlying conditions, but you probably took riskier actions, for yourself at lest, in driving anywhere than you would have by picking up a takeaway coffee. Covid isn’t magically worse than the other things that could possibly happen and there’s no need to treat it as more of a threat than it is, or to ignore other needs you have for both your physical and mental health (though I’m not suggesting a takeaway coffee is any kind of need, just that this could be around for a long time and you have a life to lead just as you did before it was around). You should incorporate the actual risk of covid causing harm into your life and not magnify it above other risks.