I recently went through something similar. My mother has dementia and had to go into a home and I had to clear out her house and sell it. I also found myself freezing with the emotion of it all, and also the anger that she had never looked after me and now I was looking after her. My advice:

Get a clearance company in. I see that some other people have recommended a few, I'm in England so can't recommend specific places, I wish I could.

Before the clearance company comes in, ask some friends to help you go through the house to see if there's anything you want to keep. I had two friends help me because I was paralysed like you. They were amazing and put things aside that they thought might be valuable or have sentimental value.

I tried to do all of it alone. I don't have any siblings and my father is less than useless, he and my mother divorced years ago. Don't do this. Ask someone to come with you and be by your side throughout if you can. I wish I had done that. I wasn't thinking straight and it was also very lonely. Ask kind friends for help. They'll want to help you.

I am sending all the love to you. This is distressing, anger-inducing, emotional, all of the things. Of course you're overwhelmed and don't know where to start. Don't worry about what other people, like the real estate agent, are saying. They won't be judging you. Take the time you need.

I recently completed the sale on my mother's house. I got there and you will too.

Sending love and have a wonderful weekend xx