Rosy, there are PH kits available at big box stores, and at nurseries. That will tell you if you can grow acid loving, or alkali loving plants.
For nutrients, probably the best way to get a true reading and valid advice is to go to your local agricultural college or your county agricultural agent, and get a soil test kit. The directions are very clear, and after you take samples you can submit them to either the college or state agency for free or for little cost. The results will tell you what you need to add in the way of nutrients/fertilizers.
Personally, I have found that adding composted manure and compost pretty well takes care of all the soil needs. What is needed is used, and what isn't needed, isn't used. Phosphorus and nitrogen are the primary fertilizers needed for our blackland prairie soils. Calcium isn't needed, since we are pretty rich in that. I don't know where you are in zone 8b, but wherever you are, you can get help in analyzing your soil and its needs.