Is there a dry top soil you can buy in a bag?

Yes, you can! Go to your local nursery and ask what varieties they have.

yes, they sell it at home depot or menards.

Unless any of the bags are stored inside they will be wet and heavy. There is no way around it. If it rains, they will get wet. About the only ones that I have seen to actually be dry are the small bags that are usually on the shelves in a store.

Do you have healthy soil before you use topsoil? Topsoil in bags is easy to find. Depending on how you're using it will depend on how much.

the top soil and compost are stored out in the parking lots in my area. with the near daily rain - nothing is dry. the bags are plastic and they hold the moisture. makes them almost double the wt. i did a lot of containers this year. i do container gardening, and had an abundance of tomato plants. 70 plants went w/ 5 gal. grow bags and potting mix to local food pantry's. fresh produce is rare at the pantry's. many pantries have no refrigeration or freezers. now...back to mixing peat pearlite topsoil and compost.