Can I go out grocery shopping ?

Yes! just wear a mask

Check with local authorities. Regulations aren't the same everywhere.

Yes. That's one of the few things we locked down people are allowed. If you're over 60, stores have a special hour for you to shop in the morning.

I don't know if you "can" (are capable of) or not. You may (are allowed to) IF your area allows it and stores are open. What people are allowed to do and the options available, vary around the world right now. 

Yes.  You may need to stand in line to get in as some stores are only allowing a certain number of shoppers at a time.  You must respect social distancing.  

It depends on the severity of your situation in your town/city/state/country. Normally yes, just be sure to wash your hands before and after shopping.

I do, gotta eat and all that, but I am not  quarantined nor do I have COVID-19