Hi, I sold my home in 2018 and split the proceeds with my ex. How do I enter this in to turbotax?

I have a 1099 S. I don't know what to enter into turbotx  premier. If the house sold for 1,000,000 and the mortgage was 200,000, the proceeds would be 800,000 split between us is 400,000. What can I enter in to turbotax to reflect a capital gains?