Short version, given what you have prior to any clarifications: In order to 'downgrade' that system (came with Windows 10 Home), you merely need to purchase Windows 7, install your new purchased OS over the previous OS *if* the hardware in said system is
supported by the manufacturer(s) with Windows 7 and install all the device drivers.
Windows 7 never had a "digital license". You have to provide a product key. If you purchased the Lenovo device with Windows 7 (not with Windows 10 - your post is fairly confusing there) - then it was the seller's responsibility to provide you with the
product key / installation media for Windows 7.
Can/will you clarify where you purchased this device from, what the invoice for the device says it comes with in terms of operating system, etc.?
I got my device with Windows 10 installed and that one month to go back to windows 7 thing was also there but i didnt have issues back then but now after a year and a half i have perfomance issues. So i know for a fact that it was windows 7 before.
I bought it from Jumbo Electronics which i authrized reseller too. They had it set up from there itself for me and they told me it was windows 7 upgraded to windows 10 using the free upgrade.The thing is that i checked that link and when i was checking how
to get that windows 7 disc to downgrade , and i saw this link https://support.microsoft.com/en-us/help/10749/windows-product-key to learn more about product key,and then i found this
Free upgrade to Windows 10. If you upgraded to Windows 10 for free from Windows 7 or Windows 8.1, you should have a digital license instead of a product key. For more info about digital licenses
in Windows 10, see Activation in Windows 10.
I clicked that blue link https://support.microsoft.com/en-us/help/12440 and it just showed me if i had a digital license or product key nothing more. So how do i downgrade now.
Thanking You
Shivram.C