What browser are you using?
When you select to install the Now Player, it actually just puts the install .exe in your Downloads folder, and you have to run that.
Though hopefully, whatever browser you are using, the Downloads alert will appear top right, a little downward arrow into a ] symbol on its back, and you can click that to see the actual downloaded file, as here:-
So you don’t need to go and find it. But you do need to click the .exe shown, which will then install the actual player, after which you should be good to go.
If you then start the resulting Player, this will offer to take you to the website, which is the only place you can choose content, and then when you choose some content, it will offer to download the Player (again!) but instead choose ‘I already have this’, and off you go.
The PC/laptop version of Now is probably the most complicated, limited, and troublesome implementation of Now out there however, so if you can, please do take @gavs82008 ‘s advice above, and see if you can watch it more straightforwardly on any other device you may own.
It’s there as native on most modern smart TVs; though if not, a Roku Express or Amazon Firestick can make any TV with a spare HDMI input as smart as you could wish for under £30.
