Linux Boots from DVD, but will not boot from my Hard Drive

[bitsnpcs]

Hello RoyTG94,

as @ptyerman wrote it sounds like you are using the live DVD and running Linux from this, rather than it being installed to your hard drive and then running it without the need for the dvd.
The external hard drive that save these settings may have a partition that enables it to run live with persistence (and save some certain settings).

Here is the installation guide for Linux Lite - https://www.linuxliteos.com/manual/install.html#instllcomp

[ptyerman]

By the sound of it you're not installing to hard drive correctly, and that's why it won't boot from from the hard drive. Any changes made including passwords created will disappear instantly on reboot when booted off CD/DVD/USB.
Do a search for Ubuntu installation tutorials on youtube and google, you will soon get the general idea.

[RoyTG94]

 
Linux Lite OS has helped me rescue my old PC, making it somewhat usable again. 
The good news is that Linux does boot.
Unfortunately, I can't load programs because I need the admin password.
I created an admin user, successfully logged in as an admin user with a password that I chose.
However, the password is not the password needed to install any software.
After shutting down my PC, all the settings, including the printer, is lost when I login again.
Before loading Linux, I completely reformatted my HD that is 450GB.
When rebooting to my HD, I get the message "No boot device found."
I tried created partitions and reformatting within Linux, but I probably only made things worse.
I'm thinking that my Hard Drive may be unrecoverable at this point.
Maybe someone can help me choose the right parameters to fix it or test it to see if it can be salvaged.
I do have an 100GB external drive that does successfully mounts and allows me to save files.
My printer is an Epson ET-2750 that does not have a driver, but the Workforce 1100 driver gets me by.
Any help on getting my netbook to boot from the Hard Drive and allow me to add software would be appreciated.
Thanks for reading this post.