Hi Hope22,
Your question is much too broad, provides too little information, and there are too many unknowns, variables, and personal preferences involved for anyone to answer what you are asking or help you choose which specific mattress may work best for you out of all the thousands of mattresses that are available in the market (see mattress firmness/comfort levels in post #2 here).
While it’s not possible for anyone to tell you “what” specific mattress to choose … the tutorial post here can help you with “how” to choose a mattress that is best for you in terms of PPP (Posture and alignment, Pressure relief, and Personal preferences) and includes all the basic information, steps, and guidelines you will need to make the best possible choice … and perhaps even more importantly know how and why to avoid the worst ones.
Phoenix