It may not be a quick fix as it sounds like you have
something draining the battery. Could be short
I suggest disconnecting the negative battery cable
from the battery and then put a test light
or multimeter between the negative post
on the battery and the negative battery cable.
If the light comes on strong you have a definite
drain in the wiring circuits.
This assumes the battery has been recharged.
Also do all these tests with the ignition key off.
Start pulling fuses or disconnecting various
connectors until the light goes out.
That will be the circuit or device that is
causing the battery draining.
Then it is a matter of finding the exact point
in the circuit that the drain is at or the
exact device that is causing it.
You should be able to narrow the drain down this
way and either repair or replace the problem.
I will be back around 4pm today if you need further help.