A +500 odds bet means that if you place a $1 bet, you would win $5 if you win the bet. The “+500” represents the American odds, also known as moneyline odds, which indicates the amount you can win on a $100 bet.
In this case, the “+500” odds mean that the team or player you are betting on is an underdog, and the sportsbook is offering a higher payout to entice people to bet on them. The higher the number, the less likely the outcome is to occur according to the sportsbook’s odds makers.