My sister and I bought a house it is in her name but for Probate reasone, we want to know if adding me to the deed will keep probate (SC) from taking the house or me having to sell the house if she dies to pay for final expences:

You shouldn't make a decision whether to be on a deed for the reason of 'final expenses' (funeral, I presume). For one thing, you never know who will die first or even if you will die together. For another, there are far more important considerations to make.

You do understand that probate is a way for anyone with a claim to assets to come forward, and shouldn't take the place of a will? The will can describe the funeral arrangements, or you can make them in advance. You should not own a home without a will, and a lawyer won't charge much to help with a simple one.

You should be on the deed if you paid for part of the house. Please explain why you didn't.

My sister and I bought a house it is in her name but for Probate reasone, we want to know if adding me to the deed will keep probate (SC) from taking the house or me having to sell the house if she dies to pay for final expences:

First, "probate" isn't an evil entity lurking out there and looking for an opportunity to grasp property from the cold hands of dead people. It is the process whereby the heirs of the dead prove their rights to property left behind. The probate court will not "take" the house in any case. It will instead, if asked, determine who gets it.

But yes, putting the property in joint ownership will probably allow it to pass to whichever of you lives the longest, without having to pay the debts of the decedent. For a few dollars you can put your mind at ease by consulting with a lawyer in South Carolina. It would be well worth the money.

If you were both listed on the deed as joint owners with rights of survivorship then if one you dies the full ownership of the property passes to the other. That does keep it out of probate. Any debts owed by your sister at her death would have to be paid for out of her other assets. However, if there is a mortgage on the property then either you will have to take over paying that mortgage yourself or sell the house.