My MacBook currently runs on Windows and I want to reinstall Mac os

Your system does not offer Internet recovery, it did offer on disk recovery accessing a hidden partition. If you formatted your drive you may have over-written the recovery partition when you installed Windows straight up.

At this point you’ll need to create a bootable USB thumb drive macOS installer from a working Mac system How to create a bootable macOS Sierra installer drive.

Then using it to boot up your system you can wipe your drive back down using Disk Utility setting up the drive with GUID partition mapping and reinstall the OS in the process the installer will re-create the hidden partition.