Subaru Strobeing Check Engine Light/Ticking Noise?

So…I’m trying to see if I can get my parts car running
Its a 1992 subaru legacy wagon, 5spd
I was going to jump the car because the battery was completely dead, so I charged it up for like 1 min,
I go in to crank it it turns over once but shuts off imediately,
And I don’t know why the battery dies after that even without the jumper cables being taken off, so I’m like wtf? Anyways, I put a 12v battery charger on it with the jumper cables still attach, I don’t know if this is a problem but I turn the key to the on position,. All the dash light work, I then hear this Ticking sound, I lsten to where its coming from and it seems to be under the steerng column, and the check engine light is strobeing like a techno party, I did a preliminary search on google and it came up as maybe a fuel pump or a alarm, I don’t have a alarm so…the fuel pump seems to be the problem. Do you guys with experience think its the fuel pump? Or something else? Like ignition relay? Or something.

i would try throwing a fully charged battery in there.
or possibly -My friends grand prix gas lines frooze so we added some unfreezer stuff and it did the job

you need a fully charged battery.