Unless you want to pay Lenovo for a recovery USB stick (if they still offer it), your best bet is searching the for a verified Lenovo OEM ISO matching your exact model and edition.
The most reliable method to get a clean, unmodified Windows 7 ISO is to use HeiDoc Windows ISO Downloader or a reputable digital archive (like the Internet Archive). lenovo windows 7 iso
Here is a proper piece on how to prepare a . Unless you want to pay Lenovo for a
Windows 7 is no longer secure for daily browsing. If you do reinstall it, keep the computer offline, use it for legacy software only, or upgrade to Windows 10/11 for anything connected to the internet. keep the computer offline