What was the purpose of the mileage?
Commuting miles, to & from work, are not deductible, at all.
Medical and charity miles are part of itemized deductions. Itemized deductions are INSTEAD of the standard deduction, not in addition to it. So, yes it's "part of your standard deduction".
Business mileage, for the self employed, is claimed on Schedule C; so that is allowed in addition to the standard deduction.