In my opinion, IF you plan on keeping the car, I would replace the tank, ( appox $125.00- $180.00 ,, PLUS Shipping costs PLUS labor ) tanks can be found through local auto parts stores, or on-line, cheaper than burning up the car or the garage & house, FUMES are BIG worry .... keep the windows open till you fix it ... be careful where you park it ......😕
looks like the hose is a little wet weep around the clamp, do you have a video of it leaking while filling the tank?
clean it all off dry and see where the wetness occurs
that is how i diagnose my Corolla fuel tank leak but it was at the very top of the tank small hose from the vent outpipe
Spray it clean with brake cleaner so you can tell how serious the leak is. Maybe you can wire brush the rust off and seal with epoxy putty. You could just find a good used tank at the salvage yard and swap it on. Careful working around gasoline. That doesn't look like an OEM pipe clamp to me, so the problem may have been developing slowly for a long time...just a guess. Lookit: https://www.maxwarehouse.com/produc..._term=4575480205951768&utm_content=Low Margin
My money is on the hose. You can try replacing that first and while it is off inspect the tank "nipple" just in case. In my experience, even some badly rusted filler parts were still intact but the rubber hoses had rotted away.
In any case, if once the hose is off the tank reveals itself to be no good the advice given by the others above to buy a used tank from a local salvage yard would be my next step. Only if no used tanks are available to you locally, then look into new (Rock Auto).