Question Window 10 rebooting

[ReL4d]

Hello guys
I have a problem with my PC
almost every time I turn my PC on, nothing will happen on my screen, it is exactly like when PC is turned off
However the case has power and seems is working normally

Sometimes by pressing a key on keyboard, screen comes up with a long delay and sometimes i can't do anything but to reboot my computer, it really sucks...

Anyway my PC is not a new one, and I don't know is this problem due to the oldness of my PC or another problem which can be fixed?

I will appreciate it if anybody help me...🙏
Thank you

 

[Colif]

Well, age isn't normally a reason computers stop working entirely.
Does it work at all if you get the screen to come up?

Is it a brand name PC? Do you know make/model? Or did you make it yourself?