Allow me to be much more succinct, per feedback received.
It seems to me that Esau clearly states, at least in his belief, that the birthright and the blessing are two separate and distinct things when he says in Gen 27:36 "Is he not rightly named Jacob? For he has supplanted me these two times. He took away my birthright, and behold, now he has taken away my blessing." Then he said, "Have you not reserved a blessing for me?"
Hebrews 12:16,17 says "...that no one be immoral or irreligious like Esau, who sold his birthright for a single meal. For you know that afterward, when he desired to inherit the blessing, he was rejected, for he found no chance to repent, though he sought it with tears."
To clarify my question for those seeking additional detail
In Genesis 27:36 Esau clearly sees his birthright (which he willingly sold for a low price) and his blessing (which was stolen by Jacob) as two separate things, but Hebrews 12:16-17 conflates the two events, ignoring the theft of the blessing, and thus appearing to conflate the two terms.
So, my question is, can anyone explain how or why the two terms are clearly conflated in Hebrews? Thanks in advance to any helpful souls out there with knowledge of the original Hebrew & Greek that might help me understand the wording of Hebrews 12:16,17.
Additions per further discussion:
It seems clear to me that the author of Hebrews has a different understanding than Esau and the author of Genesis of the meaning and application of birthright and blessings from one's father. I can only find a few places in all of the Bible where birthright is mentioned. I think the most in-depth exploration of what a birthright means is in 1st Chronicles 5:1,2 which states that Reuben lost his birthright by laying with his father's concubine in Genesis 35:22.