A full house is made of three of three of a kind and a pair. In the event of a tie the highest card value wins.
A flush is a poker hand of five of the same suit. In case of a tie, the poker hand with the highest of card will win.
A poker hand of three of a kind is three unsuited cards.
Two pairs as labelled is a poker hand of two different numbers. I didn’t make a picture so let’s try this for illustration.
Ace Ace 2 2
A pair is poker hand of two unsuited cards. A pair is also the most common winning combination. The odds get larger for getting the higher hands. If you look at the WSOP final tables, the winning hands are mostly pairs and three of a kinds.
High card is just that the highest card. Sometimes people go in looking for connectors that don’t happen. In this case, the high card becomes the winner.