Type a value in any field and the others update instantly. Decimal odds are the payout per 1 unit staked; fractional odds (e.g. 5/2) are the profit relative to the stake; American odds show either the profit on a 100 stake (positive) or the stake needed to win 100 (negative).
The implied probability is the chance of winning the odds suggest — before the bookmaker adds their margin. Comparing it against your own estimate of the real probability is the core of value betting.