Because you wiped the drive, all data including the Windows files were erased. You will have to reinstall Windows which you can do by downloading the media creation tool found here. That will create a bootable Windows installation flash drive. This support page explains the data wipe function.

And this YouTube video should help as it is a good tutorial on a clean install of Windows 10.

If you erased your hard drive, how did you think it would still be bootable?

I understood the part and have downloaded the new windows iso file on a usb thumb drive, but im not sure how to download it on the laptop itself.

If you could provide a solution to that I'd be greatful. 

This is what the laptop says, nothing else

You're better off using the Microsoft Media Creation Tool to prepare the drive.  You cannot just use the ISO -- it has to be written to the flash drive using an ISO writer otherwise.

Hi

A little light reading.

https://www.tenforums.com/tutorials/id-Installation_Upgrade/

https://www.tenforums.com/tutorials/2376-create-bootable-usb-flash-drive-install-windows-10-a.html?s=5fe68311e0733eeea79da2f7fee81535

https://www.tenforums.com/tutorials/1950-clean-install-windows-10-a.html?s=5fe68311e0733eeea79da2f7fee81535

If in doubt please ask.

So Ive downloaded the media creation tool what do i have to do next please be comprehensive as im new to this

Install it, connect a blank 16G or larger flash drive and follow the instructional prompts.

Manually select the boot device
The first thing to check is which device is selected as the primary boot. To do a quick check please use F11 to launch the manual boot selection.

Restart the system
Press F11 during POST to enter the Boot Manager
Select the correct Hard Disk drive (Virtual Drive), where the OS is installed
Boot from this device
If the system now boots into the operating system, the hardware is fine and there is a boot order conflict in the BIOS settings. The most likely cause for this is that the system is set to boot from CD/DVD and/or USB before the drives, which is a logical setting. To resolve this, just ensure you do not have a USB or CD/DVD inserted into the system.

Note: The Error can be caused by wrong settings in the boot mode, too. An OS installed in UEFI mode cannot boot in BIOS mode and vice versa.
You can change the boot order setting permanently in the System Setup to boot from the drive first. To change this:

Restart the system
Press F2 during system start to enter the System Settings
Change the Boot Sequence in the Boot Settings
Leave the menu via Exit in the upper right corner of the screen
Note: After this, you will require pressing F11 if you wish to boot from a CD/DVD or USB at a later date.

@JOcean​ So the issue is no bootable device is found. So where did you think that .iso file is going to be booted from?  From the devices that are getting the same error?  I made it to that point.  And not all Dell Inspirons have the UEFI/Legacy mode in the Bios. SOme of them do not have that option at all.  I replaced my HDD and made the .ISO file for a USBS Flash as well as a DVD disk. I formatted them in the proper win10 mode. Forgot which one.  There is no options left for me unless it's the ram, processor, or MB.  I even downloaded from dell the flash bios file.  Same thing  No bootable device. 

@JOcean​ If anyone receives no bootable device error then how can you boot the .ISO file media creation tool to start the process of installing Win10 onto a newly formatted HDD?  Will any laptop start up if it's working properly to load the necessary files to get online to download win 10 from microsoft?

@UsmanBliff​ I believe the .iso file media creation tool has the necessary files to boot transfer to the newly frmatted hdd and get online to download win 20 from microsoft.  I'm not sure but That's the only way I know how. I've nevr gotten this issue until now. I just wan tto install win 10 on a laptop to give to a friend who has dementia in an assisted iiving. 

@ejn63​ So the .iso bootable media creation tool needs an iso file writer for it to boot?  That's a first for me to hear.  Microsoft never even mentioned this.

You don't need a separate ISO writer -- just use the Media Creation Tool, which will directly prepare the boot media for you.