PLO looks like Hold'em with extra cards, and the extra cards mean bigger hands and huge draws. The one rule that trips everyone up: exactly two from your hand, exactly three from the board. No more, no fewer.
Every game here uses Dojo Coin: play money with no real-world value. You can buy it with Buy Coin (not sold in Washington state), but you can't cash it out. It's just for practice.
If everyone else folds, the last player wins the pot without showing. Heads-up: the button posts the small blind and acts first preflop; after the flop the big blind acts first.

On your turn you can check (if nobody has bet), bet, call, raise or fold. If you could check for free, the site checks for you instead of folding.

Example: blinds 50/100, pot 150, you're first in. Call 100 (pot is now 250), then raise 250 more. Your pot-size raise goes to 350.
Same high-hand rankings as Hold'em, from royal flush down to high card. See the full hand rankings table.
The one-heart "flush." Board 9♥ 6♥ 2♥ K♥ 4♣, you hold A♥ J♠ J♦ 8♣. Only one heart in your hand, so no flush. Your best is a pair of jacks.
The one-card straight. Board 5♣ 6♦ 7♠ 8♥ Q♣, you hold 9♠ A♦ A♣ K♥. One nine isn't enough: the second hole card has to fit too. Best hand: a pair of aces.
Trips on board. Board Q♠ Q♦ Q♣ 5♥ 5♠. You can only use three board cards, so you need a pair in your hand (or a queen plus another card) to make a full house.
Exactly two of your four hole cards, plus exactly three of the five board cards. Never one, never three.
Call the current bet first, then raise by the size of the whole pot after that call. Pot-size raise = current bet + pot after your call. The Pot button does it for you.
No. PLO uses the same high-hand rankings as Hold'em. Only which cards you may use is different.
Only if you hold two cards of that suit. One suited card is never enough in Omaha.