Can I deduct services such as nail preparation if I can no longer do it for myself

Only if the doctor prescribes it and you have enough total deductions to itemize.  

You can only deduct the amount of unreimbursed Medical Expenses you actually paid over 7.5% of your AGI.  And then all your itemized deductions have to be more than the standard deduction to get any benefit (so you would only be getting the benefit of the amount that puts you over the standard deduction).  And since the Standard Deduction is increased more people will not need to Itemize.

For 2022 the standard deduction amounts are:

Single 12,950 + 1,750 or 65 and over or blind (14,700)

HOH 19,400 + 1,750 for 65 and over or blind

Joint 25,900 + 1,400 for each 65 and over or blind

Married filing Separate 12,950 + 1,400 for 65 and over or blind