Installing Mac OS Mojave error

Hey guys,

I currently own an early 2015 Retina Macbook Pro and I am currently running into what is supposedly software issues.

The issue started when my Mac was acting up with a few things; Graphics processing (Pixelated). This would occur a number of times. Being fed up with this I could see that there is a pending update through the App Store for OS x El Capitan 10.11.2 to which I then proceed to attempt to update. I run into a number of issues through the App Store where either the download would not complete or would not verify. I then proceeded to restart it a few times and reset the SMC and PRAM alongside. Through a combinations of resetting the download finally completes and I am now at 10.11.2. After that I then check the App Store again to find any updates and find that I am able to download Mojave to which I then proceed to do. Through the middle of updating, a message then pops up stating that there has been an error with removing the previous OS and that the instalation has failed informing me to restart the process. I restart the process, ensure the disk has been verified and repaired and still proceed to get the same message.

After a few attempts I attempt to restore it via Time Machine but there are no available backups. I boot the Mac back into internet recovery and instead of the Mojave installer, I am greeted with the OS X Yosemite installer instead to which i attempt to install only to find out that the drive has randomly disappeared from the system installer. Also having checked the start up disk, it also appears empty.

What I wanted to know was, can anything on the drive be saved? or are all my files dead? This meaning that there are no options when I go to the start up disk alongside with the Yosemite installer and having the disk being blank?