You should only need to type "espn3.com" (without the quotes) in your browser and then look for today's live events.
If you are using a cell phone, you should be able to install the ESPN app and use that. (Not positive if you can install the app on a laptop, tablet or PC, I have never tried.)
Try to access ESPN3 about 10 minutes before game time because you may have to jump through some hoops to finally get to the game.
Phil, do you now have Cable TV (Comcast, Frontier, Cox...etc or the equivalent live TV streaming service (YouTube TV, Sling, FUBO TV...etc that carries the ESPN channels?)
If I'm not mistaken, in order for someone to be able to watch the content on ESPN3, you must already be a subscriber to the ESPN and ESPN2 channels supplied by your cable/live streaming TV services. If you install the ESPN App (see below), upon login they want the authentication from your current Cable/Live streaming TV provider.
ESPN3 and WatchESPN...both of these are now integrated in the "new" ESPN App (not the channel but an app downloaded and installed on a computer, smartphone, tablet, Smart TV with apps and ROKU, Fire stick...etc).