Why would a laptop turn off after 15 seconds?

I have a laptop that my late father bought for us. Today, after owning it for about 6-7 years, it won’t turn on. Or rather, it turns on, and after 15 seconds, it turns off.

The screen never comes on in that time. Even though I worked in IT for 5 years (a while ago, admittedly), I’ve never seen this, nor learned any skills on even beginning to diagnose.

Any and all tips most welcome. It may be old, but in terms of spec, even something equivalent, today, would be way more than we can afford at the moment (no sob story, I promise), and would disrupt our life significantly so I want to put due diligence in repairing before considering replacing. Especially given that my PC is currently going through its own problems at the moment…

It is an AORUS laptop, with a GTX 1080 in it. I’m not really sure what other specs are relevant. I just want to figure out why it’s immediately going off.