The Child and Dependent Care Tax Credit can only be used toward care of a disabled spouse if the reason you needed to pay for care was so you could go to work.
Many of your expenses will be deductible as medical expenses, although there are some limitation that may mean you don't get as much actual tax benefit as you expect.
You can list medical care, medication, nursing and rehab. For in-home caregivers, you can deduct the part of their carer that is for medical and nursing services. Nursing services do not have to be performed by a nurse, but they must be the kind of services usually performed by a nurse, such as assisting with dressing, bathing, toileting, eating, and providing medical care and medication. Costs for companionship, meal preparation, house cleaning, laundry and so on, are not deductible medical expenses. If your care providers performed both medical and non-medical services, you must decide what percentage of their cost was from medical care only.
You can only deduct expenses actually paid for in 2021, you would have to deduct past expenses on past tax returns.
There is a specific section on the Deductions and Credits page to list your medical expenses. You can also include your premiums for medical insurance including Medicare part B, C and D, as well as your own costs for medical care and medication. It may or may not reduce your taxes owed, depending on your other income and deductions for things like a mortgage, property taxes, and gifts to charity. Be sure to list all your itemized deductions, even if you usually skip that section, because it may help you get some benefit from the medical expenses.
