your not asking for a lot are you.
First we need to know what type of computer you're using. Mainly the type of monitor you have.
is it a CGA, EGA, PGA, VGA, SVGA or something else.
CGA is easy to adapt using basic logic circuits. EGA is a little bit harder because of the frequency but not impossible. VGA and SVGA runs at a much higher frequency it normally requires a frequency converter for this. converters for VGA and SVGA are available but they're getting hard to find and normally the picture quality is not quite as good. It might be better just to get a video card that has a TV out made into it.