Your “cost” basis of he property that you sold is the value on the date of death of the person who left it to you. So, for example, no matter how long they owned it, and no matter what THEIR original cost was — your cost was an estimate of the value on the date they DIED.
So if you sold it as quickly as possible after inheriting it, you would likely have NO taxes on the sale. YOu’ll need a bit of help from a tax preparer to file a separate schedule when you do your taxes for 2020 next spring.
If you inherited it a longer time ago, you might need to get an appraisal of what the property would have been worth when you inherited it. But you’re not likely to get audited on this!