YES - Handling the food should be safe. The virus can live on inanimate objects, so wash hands before eating. With delivery, arrange that driver leaves food on porch & wait until they're 6 ft away to open door & receive food.
It is safe. Simply wash your hands for 20 seconds with soap and water after.
Try to avoid crowds & keep 6 ft distance between yourself & other shoppers. Some stores have special hrs for the elderly who are particularly high risk for severe disease from COVID-19. Again, wash hands after shopping.
Lice check, routine dental visits & screening mammograms are non-essential. If unsure whether your scheduled procedure is essential, contact the individual with whom you're scheduled & discuss.
We don't know for sure about immunity after infection. While one does make antibodies to COVID-19, there are reports of re-infection after recovery from China & Japan. Once you recover, assume you're susceptible.
Like any delivery, wash hands well after handling. No harm in wiping down the books with disinfectant wipes or diluted bleach at 1 part bleach to 100 parts water.
If your jurisdiction allows, your family can safely go to an empty beach or large park, as long as you socially distance from other families at least 6 ft away.