i removed the canister under the hood, it would sit opposite the battery, and it would be on the driver's side.

there was a hose, labeled "TANK" and it ran to a hard line

as you can see in the pic, i have plugged this with a bolt.

is that ok?? after driving the car i can hear the air hissing out of it.

is that the only vent for the tank?

 

Yes, unless you replace your gas cap with a vented one.