This is the 104th most frequent Italian word.
tanto
"Much," "so much," "so many," "so," or "a lot."
In this sentence, 'tanto' is used as a quantifier indicating the amount of information to share.
Ho tanto da raccontarti.
I have so much to tell you.
Here, 'tanto' conveys a sense of inevitability or that the effort could be beneficial.
Tanto vale provare.
It is worth trying.
In this case, 'tanto' emphasizes the depth or intensity of affection.