Hey i have a road fixed gear conversion non-horizontal drop-outs
i was wondering if its possible to put a chain tensioner on it
and if so how?

if it's actually a fixed gear, no. At least not for long.

if it's a single speed, yes.

First, the idea behind a chain tensioner is to keep a wheel from moving horizontally. With vertical dropouts, like yours, a wheel cannot move horizontally and so a chain tensioner is not necessary.

If your asking about using a hanger that takes up the excess tension in a chain on a singlespeed, then Straws is correct, you can only use that on a singlespeed. If you put it on fixed gear bike the hanger would break almost immediately.

not quite.. it would fail when you put back pressure on