One of the things holding back a potential hackintosher from trying to hackintosh or install macOS on their PC is that they have only one hard drive and that hard drive already has Windows installed on it with no secondary backup or second drive to spare. There is actually a way to install macOS on a drive that already has Windows installed on it without having to delete Windows, but this will only work if the Windows disk is GPT formatted. Step 1: Verify GPT Partition Type Install MiniTool Partition Wizard Free Edition Open MiniTool Partition Wizard Verify your Disk is GPT
Source: Dual-Boot macOS on a drive with Windows 10 already installed (Shared Drive) – Hackintosher