When it's time to turn on the Xbox it starts and after 10 seconds it turns itself off.

Hi Brad,

The turning off is a common problem with my xbox due to poor ventilation, but it always turns back on automatically by itself. When I turned it off after it restarted as normal, it is now not turning on anymore, instead turning on for a second and turning
itself off again

Have you tried a "Hard" Restart?

Press and hold the power button on the Xbox itself for 10 seconds. After it turns off, wait about 30 seconds, and then press the power button again to turn it back on. This seems to fix
most of the "too long to start" problems that I have had.

Good Luck!

Mine is doing the exact same thing, only had it since XMAS but every day for the last week when I power the console on it starts for say 10 seconds then turns itself off.

When I turn it back on again it's like it's booting from a cold start, it's frustrating.

Also when I tryed to turn it on it would turn on but after 10 second it would turn off again.

Hi there,

as you have ensured your console is not overheating and has adequate ventilation, this may be an issue with your console's power supply. Please visit this page: https://support.xbox.com/en-US/xbox-one/system/console-wont-power-on/
and check through solutions 4, 6 and 7. If none of these help, solution 8 may be your only option (having the power supply replaced).

Let us know how you get on! Good luck.