You give so little information that is is impossible to give you any useful advice based on this question. Similar to asking a CPA so what do I need to know about taxes if I make some income? Where would one even start without knowing a whole lot more....
My answer is not intended to be giving legal advice and this topic can be a complex area where the advice of a licensed attorney in your State should be obtained.
mr corrigan is correct. you should consult with a lawyer who is familiar with probate and foreclosure law. you will need to bring to him copies of the foreclosure suit, note, mortgage, will and any correspondence regarding these items. then a lawyer can answer your question. but without the documents and knowing what it is you are concerned with there is no way anyone can provide you better answers
without a detailed review by a lawyer can all the issues raised in your question be appropriately addressed...nothing in this response should be construed as establishing a lawyer client relationship..the answers herein are for informational purposes and not to be construed as advice
You need to consult with a probate attorney who is also knowledgeable with foreclosure law. Ideally you will want to meet with an attorney who practices in the county where your father resided at the time of his death.