> Eventually you'll need to interact to some degree with others when getting groceries etc.
The main risk when getting groceries, unless people are coughing or sneezing in your face, is transfers from your hands, which a surgical or n95/r95/p95 mask does roughly zero to help with. (Now, getting everyone else to wear such a mask would reduce the odds of them contaminating something that would get on your hands, but that's not a benefit of you wearing mask.)
The main risk when getting groceries, unless people are coughing or sneezing in your face, is transfers from your hands, which a surgical or n95/r95/p95 mask does roughly zero to help with. (Now, getting everyone else to wear such a mask would reduce the odds of them contaminating something that would get on your hands, but that's not a benefit of you wearing mask.)