Yes they can.
They can take up to 15% of your social security.
Before they can do so, they have to notify you by mailing an Intent to Levy. You will also receive a CP 91, an IRS notice with the ominous title “Final Notice Before Levy on Social Security Benefits.” Take it seriously. You have only 30 days to respond before the IRS is able to levy you.
Once levied you will have to pay up in full, set up a payment plan, propose an offer or move the account to CNC (cannot collect) status.