To watch your favorite - and local - NFL team's games all you really need is an OTA Antenna.
"Which type of antenna do I need?" you ask?
This is NoCable.org's specialty. Enter your home address on our homepage, or use our handy-dandy guesstimator, and we will tell you exactly which antenna to buy. If you hop over to the "Sports" tab once you've gotten your OTA report, we can walk you through how to get all the other sports teams in your area as well.
Potential Blackout Alert! For watching Out of Market teams, you will need to subscribe to one of NFL's official services. DirecTV has 'Sunday Ticket', Dish has 'NFL Redzone' and other cable services have their own. Since this is a cord-cutting website, you will need to subscribe to NFL Now Live, which allows you to stream any out-of-market game from anywhere you are.
For watching Monday Night Football, you will need access to ESPN. ESPN is of course a Cable TV channel, but you can get it through a few different streaming services such as Sling TV and DirecTV Now. The ESPN channel is a part of each of their base packages, which at the time of this article is $20 for Sling TV and $35 for DirecTV now.
If you are looking to watch only one game, then you can probably get away with signing up for each of their free trial time period, and then cancelling shortly thereafter. You can get Sling TV's 7-day free trial here.