Unable to boot SSD after installation. Bios all Greyed Out

Hi Everyone,

I was unable to boot the window in Bios because all my settings inside Bios mostly greyed out. (Cannot able/ disable secure boot.

I did found one forum they mentioned to change/ insert the admin password, but i was unable to do all these. As per the admin password column they mention the old password was not set (as per picture 2), after i set the password automatically popped out (as per picture 3) required me to insert the old password (what is the old password actually. I did try to inserted the password i inserted during picture 2 situation, but "wrong old password" popped out.

Here are my questions,

1. How to disable secure boot? That selection column all greyed out.

2. Did the admin password not set causing the greyed out of all Bios settings?

My Laptop Info,

Dell Vostro 5468

Bios Version 1.12

Any help is going to be appreciated, THANK YOU!