What are Intermolecular hydrogen bonding and Intramolecular hydrogen bonding responsible for? Their effects on properties of the compound?

Q. Ice float on water. Which hydrogen bond is responsible for this? Intermolecular hydrogen bond or intramolecular hydrogen bond.

Q. Which of the following compound(s) have intramolecular hydrogen bonding?

Q. Hydrogen bonding is of two types - $t$ Intramolecular and intermolecular Am I right ?

Q. Ortho-nitrophenol is steam volatile whereas para-nitrophenol is not. This is due to
$1.$Intramolecular hydrogen bonding present in ortho-nitrophenol
$2.$Intermolecular hydrogen bonding present in para-nitrophenol
$3.$Intramolecular hydrogen bonding present in para-nitrophenol
$4.$Inter-molecular hydrogen bonding present in ortho-nitrophenol.

Q. The intramolecular hydrogen bonding in compound leads to: