As a F-1 visa holder, you are considered as "exempt" meaning not counting days for five years starting from the date of your first arrival in the United States. After the five years period, you will start counting days by using the Substantial Presence Test to see if you qualify to be treated as a US resident for tax purposes. If you are within the five years period of time frame, you are not entitled to pay any FICA taxes. You will need to file a Form 843 to claim the withholding back. However, if you are on F-1 visa including OPT for more than 5 calendar years, you are not exempt from FICA taxes.
https://www.irs.gov/uac/form-843-claim-for-refund-and-request-for-abatement
As a F-1 visa holder, you are considered as "exempt" meaning not counting days for five years starting from the date of your first arrival in the United States. After the five years period, you will start counting days by using the Substantial Presence Test to see if you qualify to be treated as a US resident for tax purposes. If you are within the five years period of time frame, you are not entitled to pay any FICA taxes. You will need to file a Form 843 to claim the withholding back. However, if you are on F-1 visa including OPT for more than 5 calendar years, you are not exempt from FICA taxes.
https://www.irs.gov/uac/form-843-claim-for-refund-and-request-for-abatement