You can get splitter boxes. Ask at your friendly computer store they will be using one to power all the display monitors you see for sale.
You can get extension cables for VGA, but you can introduce ghosts on the picture.
I use an old computer for displaying slides on TV
Or sandisk do a thing to connect your memory cards from your camera to the TV red, white & yellow sockets. It is Called Sandisk Photo Album, I bought mine for about £19.00