See this TurboTax support FAQ for reimbursing SS taxes withheld - https://ttlc.intuit.com/turbotax-support/en-us/help-article/social-security-taxes/get-refund-excess-...
Look at your W-2 for the Medicare taxes withheld. Multiply the amount in box 5 by 1.45%, that should be the amount in box 6.
