Hello, I’m Nathan, and I’ll be assisting you today. My livelihood depends on your positive feedback, so your satisfaction is my highest priority.
Sorry to hear you’re having trouble.
These are 2 separate things here.
Your tv is an older model and does not possess any "smart" features of its own. The tv is not capable of connecting to wifi/internet directly.
That is the purpose of the external box. As long as that box is connected to the tv with a hdmi cable, and the tv is set to the proper input, you can use the content available through it.
However, the bravia internet video link device you have is extremely limited in scope. It is slow, and has low quality video (not HD), and the content available is limited to the sony VOD service. It won't give you things like youtube, amazon instant video, netflix, etc.
You would be much better served to forget about the sony box and spend $30-100 on a chromecast, roku, appletv, fire tv, htpc or smart bluray player and get all the same functions and many more, with better performance and lower cost. Of these options, the firetv is the most capable.