@bevinsamuel you are not telling us if your computer uses a HDD or a SSD. Whichever one it is, it looks like it has failed. You will get that message when your computer can't find the boot drive. You can check the computer's BIOS and let us know if [link|https://www.dell.com/support/manuals/en-us/vostro-15-3568-laptop/dell_vostro15_3568/entering-bios-setup?guid=guid-f64cd182-5252-462e-80b2-cb92f26a2704&lang=en-us|the BIOS] still finds a drive.
While in the BIOS, set your boot order to USB first. Now get a bootable USB drive and see if your computer boots with that. If so, you know you will need to replace your HDD/SSD and reinstall your OS (I assume you are using Windows)
To work on your computer, this [document|42033] should work for your model as well. Of course, this guide [guide|132110] is even better!