How can I buy my real estate taxes back and save my property?

Find out who manages the tax sales. Call them. Ask them your question. Some jurisdictions may want you to bring all your taxes current. I don't think you should worry about that. Your main job is to redeem your property before it goes to foreclosure. If January is the date, you best pay it off as soon as you can.

The current taxes don't have to be paid yet. If you default on them, the taxing authority will have to bring another action to foreclose and you will have an extended period in which to raise the money to pay that separate bill.

Call the taxing authorities immediately and get the right answer. You don't need this preying on your mind any more. Find out what their rules are, and move ahead.