Please look at this video.
I've watched a video on youtube that showed me how to fix the power jack but it still does the same thing.
the battery should be full by now so that's not the problem.
Now my laptop turns on and off by itself.
I'm sorry but that video doesn't help us at all. What was the problem with your power jack?
And no the battery shouldn't matter, actually you should take out the battery because if it works as it should it will start without the battery when the cable is connected.
A computer not starting can be for several reasons, all being hardware related of course. Do you have any warranty left? If so, use it. If not, considered paying for getting it repaired.
I don't know what help you got from the video but it seems pointless to me.
Do you know somebody with the same laptop? You could swap your battery with one that's charged. If it still doesn't work it's probably not the DC jack.
Is the power supply original or a replacement? If a replacement isn't right for your laptop the tip of the jack plug might be too short or the internal diameter might be too large to make good electrical contact.
If the DC jack socket is damaged it's a major job involving disassembly. If the socket is soldered to the motherboard (some plug in on a short length of cable) it's difficult to desolder it without causing damage. Best left to a technician.
you got the power cable in, but there is no indication light/LED saying the battery is charging or that it's getting power.
the video doesn't really help beyond that.
have you tried a different power adapter/charger. it's usually the main cause, the power jack going bad is more common in older laptops, they have been redesigned to minimised the power jack going bad in the laptop.
what did you do to repair it? what was the problem that caused to to fix it or suspect the power jack was the problem??
The problem might not be related to the power jack. We know nothing about the cause. Since fixing the jack didn't fix the problem, obviously the problem is somewhere else.
There's some clown who keeps pressing the on/off button.
How do I stop the default from zooming all the time?