I accidentally chose the other operating system as default system, now laptop is turning on and off

[o71]

Product Name: HP Laptop 15s-du3xxx

Product Number: 46R38PA#UUF

Context before I head unto the issue:

A notification about the new system or something popped up and I installed it and restart my laptop. After the installation was done, I opened my laptop and gave me two (2) options of operating system (note: both of it had the exact same name or something). I chose the first (1st) option and it function like it normally did - like logging in, etc.

Now unto the issue:

Today, as I opened my laptop, I was trying to find the option to just have this operating system as my default and I had to choose again from the two (2) operating system options and I accidentally chose the second (2nd) option. Now, my laptop just turn on and off every two (2) seconds. I thought of changing the default operating system but I do not know how. I searched in the internet where it said it should be seen in the 'Boot Options' but  I do not see any settings or something that can make it change. Also, though it flickers on and off, I can still use the F# keys. 

Thank you in advance and I am sorry for the long message. Just wanna be thorough and transparent about the things I did before the issue happened.

[BeemerBiker]

I am not sure what the problem is.  Normally a notification like you described is for a windows feature update and not an operating system install or reset

Have you run diagnostics?

Tap the ESC key after powering on.
Tap it once a second after you see the LEDs on the keyboard flash.
When you see the startup menu, press F2 to run diagnostics.
If a component fails during the UEFI test then
Click here to check warranty and Click here for world-wide contact info

Do you have backups of your work: one drive, cloud or local storage backup?

If you have backups you can do a factory restore and then get your backups put in

Cloud recovery provides all the custom HP drivers.
Go to the below site and enter your product ID including the 3 characters after the # character
It may take an hour or more to create the recovery USB and you must use a PC that you have admin rights on.
https://d34z73bbtpzgej.cloudfront.net/
Alternately, download from the MS windows store
Click here for instructions.

If you do not want to do a cloud or factory restore then try booting in windows safe mode and pick a restore point that has a date before that notification arrived

Since Windows cannot start then you need to enter Windows safe mode from outside of Windows

Hold down the shift key and turn the power on. If windows does not shart in save mode then read this article about safe mode. Skip down to 'Enter safe mode from outside windows. If F11 does not get you into system recovery then try turning the power on and off three or more times in a row.

Select the restore point.
Clicking on "System restore" will bring up the list of restore points similar to what is in the below video.
https://www.youtube.com/watch?v=sixGAIiPTlE

If there are no restore points let me know