As someone who only dabbles in the tech world, I would like to know if this sounds reasonable to anyone else...

In my new home there is kinda communal / public wifi, but the signal is too weak to reach my bit properly. In my living room there is an ethernet plug which works (*waves from The Internet*). I can just get my own cheap wifi router, right? And then it would be secured to me rather than public. And then if I got a Chromecast that would also be secure to me rather than potentially mingling with every Tom, Dick, and Harry?

Edit - thanks guys! Basic router and chromecast ordered. And I even checked that my telly has a HDMI socket....