I want to purchase propery in US and my dad (who lives in another country) wants to help by sending me some money (assuming 50K to 100K). How can I go about achieving this

Just do a wire transfer between your father's bank and your U.S. bank.

You MAY have to submit Form 3520 to identify the source of the funds, but no taxes will be due from the U.S. side of the transaction.

Hi AtlantaTaxExpert,

What about the fund transfer from a third party from my dad to US to buy house.

Again, not taxes will be due, assuming your father is a non-resident alien.