My dad passed away on January 17, 2020. I'm his sole heir. How can I get pro Bini help with getting the property probated?

In Texas probating your father's estate may cost less than you imagine.  You will need the help of a probate attorney who practices in the county in which your father died.  If he left no Will but no more than a home, up to $60,000 in personal property and up to $75,000 in other property (such as a bank account), you may be able to file a Small Estate Affidavit.  Otherwise, you will need to probate the Will or file an Application for Determination of Heirship and Issuance of Letters of Administration.  Depending on how much cash is in the estate and how much debt there is, you might find a lawyer who will represent you in exchange for payment out of the estate.  If your income is low enough, you may qualify for pro bono representation through Volunteer Legal Services in your area.