Windows 10 Media Toolkit in an USB and reinstall it again.
Do you mean the windows media creation tool? Did you use it to make a Win 10 installer?
Format feature? the simplest way to reinstall win 10 is to do a clean install, it includes, as part of its process, a complete wipe of the ssd without the need to format it first.
boot from installer
follow this guide:
Win 10 Fresh install guide
when you reach the screen asking for licence, click "I don't have a key" and win 10 will continue to install and reactivate once finished
Secure erase is usually a feature built into the BIOS, you don't need an operating system to use it.
otherwise you can wipe ssd using this:
change boot order so USB is first, hdd second
boot from installer
on screen after languages, choose repair this pc, not install.
choose troubleshoot
choose advanced
choose command prompt
type
diskpart and press enter
type
list disk and press enter
this shows all drives available, DVD/USB and hdd, make note of hdd number
type
Select disk X - where X is the number of the hdd you want to wipe, change X to that number and press enter
once the drive you want to wipe is chosen, type
Clean