How do I restore my forgotten password if I don’t have any Macbook?
How do I restore my iphone without using a Mackbook
iPhone 6s Plus, iOS 15
Question marked as
You don't need a Mac to use the procedure in If you forgot your iPhone passcode - Apple Support
You can also use a Windows PC that has iTunes installed.
Also see the following from that support page:
If you don't have a computer and you can't borrow one, you need to go to an Apple Retail Store or Apple Authorized Service Provider for help.