This is not a PC but a TV and there are limits to the browser. If you want a site to play on your TV the site has to be careful in their setup to tailor it for play on the TV.
As to the keyboard, many work but folk need to try a few. Logitech units seem to work a lot.
When using Internet via Samsung 8000 series it won't allow input of characters in search engines, etc., and when I tried to install adobe flashplayer it wouldn't accept any version and wouldn't load. Wanted to live stream a basketball game and wasn't able to do it because of above problems. Ideas? What am I not doing that will allow keyboard/mouse to sync with TV screen? Thanks!