Q: My iMac won't start up!, I accidentally erased the base system

A little Background: I had just bought an iMac desktop second hand, an older model that was still fairly recent  and had El Caption already installed by the seller and it worked fine when it arrived.

despite it being mostly untouched, I wanted to clean out any files the the seller possibly would've on it and I went into Recovery (Where you hold down control + r) to attempt the iMac to it's original factory settings

I clicked "Disk Utility" then went on "Internal" and clicked "Erase" and thought that would do the trick

clearly it didn't and was having start up trouble

After awhile I go back on and back to disk utility and clicked "Restore" and "Enable Journaling" and I thought that helped but it didn't

So every time I try to start it up the start up page will fully load but won't go into the login menu

Is there any advice for me to get my iMac working again?