Hood release cable not attached to release mechanism under the hood. Can the hood be popped (opened) from front?? . Battery went dead and when I tried to open the hood the cable was loose (detached)

The hood release is not affected by the battery. Under the dashboard on the driver's side there is a small pull lever that releases the main latch for the hood.
Open the car door wide and put your head in the foot well and look up. The lever will have a marker on it like the first attached picture.
When pulled the hood should 'pop' open. Move to the front of the car and look between the slots in the front grill. There should be a pull tag, (picture 2), to release the second latch.
When you re-close the hood push 'Both' sides of the hood down as it can flex and not lock properly.

Heidi, No electric release. The latch is probably stuck. While you pull the interior hood release have an assistant push down and pull up repeatably/vigorously until hood releases from stuck position. Lube latch and cable before closing hood. Check the attached links,instruction and guides, Good luck
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What is wrong with hood release?
Sometimes I use vice-grips on hood release cable, have a helper standing at the end of the hood. At the same time you pull the release cable, have the helper pop the hood in area of release mechanism with palm of hand, sometimes that works to open hood. If you get it up, lube everything.
Some makes and models, I can remove front grille and reach the release mechanism. Don't know about your vehicle?

I would check to see if the hood release moves when the inside lever is pulled then pushed, if not the cable and latch mechanism may need lubrication or be broken.

If the plastic hood release handle inside is broken, can you reach the steel cable, if so, use a pair of vice grips to grab the cable and pull. Sometimes it helps to have a helper standing at the end of the hood and pop the hood with palm of hand, in the area of under hood release mechanism, at the same time your pulling the cable.

If cable is broken, some makes and models, you can remove front grille and get at under hood release mechanism.

There is usually a primary hood release, inside vehicle, and a secondary release under the hood, you have to slide your hand under the hood to release, sometimes you have to press down on the hood a little to move release. Trying to shut the hood with secondary release engaged can be difficult, you don't have the distance and the weight of hood to swing down.

try to reach up under the front of the car with your arm and try to locate the latch with the hood release cable attached to it. Use your fingers or plyers to manipulate the latch to release-pull on the cable. You may have to remove the grill to access it.

If it is not popping up at all, have someone "Thump" on the front of the hood with their hand while you pull the hood release cable. This will usually get it to pop up. Yes there is a secondary release. All hoods have secondary releases you can reach up under the hood to get to it once the hood has popped up from the first release.
Once you get the hood open, spray the latch mechanism with silicone lubricant to make it easier the next time.

The only thing I can think of is to crawl under the car and with a flashlight and something long enough to reach the cable, try to pull it down to where you can get a hold of it. Good luck.

Sometimes it helps to have a helper standing at the end of the hood, as you pull the hood release mechanism inside, have the helper pop the hood with palm of hand in area of release mechanism. I haven't looked to see if you could remove front grille?
If there is a national brand autostore in your community, they have been known to make house calls. Possibly, they could raise your hood, replace the battery or give it a charge, whatever. I don't know what they charge?
Sometimes you can charge your battery by hooking up battery charger to battery cable at your starter motor?

find the cable that is supposed to attach to the latch, and grab it with a pair of pliers or the like and pull.