My dad cousin is my friends dads brother r we related?? If so how far down r we related and if its like 3rd/4th cousin is it legal to have a relasionship ***?

In some States it's legal to have a sexual relationship - and marry - a first cousin. I assume that's your question - ? It's interesting to figure out the family tree but it's not necessary.

What State or country?

So your friend's dad is a first cousin of your dad, which would mean your friend is your second cousin, and your friend's dad is your first cousin once removed.

Assuming there are no half brothers or sisters in the generations before you, then yes, you and your friend are related.

Your dad's cousin (your friend's uncle) is your second cousin. You can marry in any state in the US.

Oops, anyway it's OK to marry

I'm in the uk... his dads brother is my dads cousin the brother don't share th same dad.

I'm in the uk .

Sorry I wasn't clear the friends dads brother same mother differnent dad is my dads cousin.