Form 1310

I am the executor for my mother's estate and she is due an IRS refund for 2020. There is no probate or estate accounts set up, I have her will stating that I am her executor but the directions ask for form 1310 and court certificate showing I am her representative. Nothing went to court, her will was certified and filed with the state of Washington but no further action  was needed. What do I need to send the IRS?

Kim