The 2020 Monday Night Football season will be available on ESPN in the U.S. You can watch ESPN online on five of the largest live TV streaming services.
Hulu + Live TV and some of the other services offer a variety of free trials, and it includes ESPN. Hulu also has tons of other live sports channels to watch a full Sunday of NFL action, along with other popular sports. (See all Hulu with Live TV channels.)
https://www.game.tv/tournaments/gameMinnesota-Vikings-vs-Chicago-Bears-live-stream-free–54ed28e6f2ff45409b3bebdc9dc4d41c