How can I put the TV on input w/out the remote?

it depends on what is on the tv casing? if you only have channel buttons then you will not be able to watch dvd through the av inputs-but all is not lost-most universal remotes accomodate for av inputs on tv's so it might be worth investing in one of those.

prehaps advertise the type of tv brand and model and ask someone if they meet with you to allow you to use a remote control that learns the signals of the original. maybe even a store still sells that model and so they might let you program a new programmable controller off one of theres.

you should have a menu button on ur tv , if not , you may have to purchase a universal remote to replace the lost one

If the TV has a viedo button, then you can use that to change between inputs.

you can't