Hello!
I can not do the translation because I do not speak this language - sorry!
"Hell yeah" - means I strongly agree (this is a very informal expression and should not be used in a formal spoken exam or written in an essay!)
"Too good to be true" - It is so good that I don't believe it - I am very happy! Example: I'm go to buy a car that I really want and when I get to the garage, they have just started a sale (the car is a lot cheaper than I thought it was going to be) - it is too good to be true!