Hi Lynsi
I am Dave, an Independent Advisor, I will help you with this . . .
That USB you refer to, is that a bootable Windows 10 USB?
If so, insert that USB drive into your laptop, then start your laptop, and on the Dell logo screen, repeatedly press the F12 key
Does that bring up the temp boot menu, if so, select that USB drive as the boot device
Then, when your laptop boots form the USB, rather than installing Windows 10, choose 'Repair this Computer'
That will give you access to the Recovery Environment, work your way through the available options in there . . .
Go to Troubleshoot - Advanced Option - Startup Repair
See if Windows startup can repair itself
Go to Troubleshoot - Advanced Option - System Restore
Check to see if you have a restore point you can go back to
If you do not have a Restore Point, go to Troubleshoot - Advanced Option - Startup Settings and click Restart
Upon restart, press 4 to enter Safe Mode
Once in Safe Mode, backup your data if you do not already have a backup
Open Device Manager and check to make sure all your Drivers are up to date
Reboot to see if Windows will start Normally
If the above fails, go to Troubleshoot - Advanced Options - Reset this PC
Choose to keep your files and apps, just your files or to keep nothing
Then start the Reset