The payout for a $100 bet on an NFL moneyline depends on the odds being offered by the sportsbook for a given bet.
Odds denoted by a "-" in front of the line usually represent the favorite on the moneyline. If you see a line that lists the Kansas City Chiefs at (-200), you'll win $100 for every $200 wagered on the Cheifs if they win.
Let's say the Cheifs are favored against the Las Vegas Raiders, with the Raiders listed at (+160) on the moneyline. The (+160) odds mean you'll win $160 for every $100 bet on the Raiders if they win.
If you're betting at an online sportsbook, your betslip will automatically display the potential payout for any bet before you send the bet through to the sportsbook.