Ok firstly, they are both Personal Computers (PC), what you have is two desktop PC's with different Operating Systems that like to use different protocols. Windows use's Server Messaging Block (SMB) while Apple, being based on BSD, likes Network File System (NFS) or Apple's own Apple Filing Protocol (AFP). NFS and AFP aren't going to work here without you having much greater knowledge, but Common Internet File System (CIFS) is compatible with Microsoft's SMB and something that pretty much everything can understand. So we're going to use CIFS as our sharing protocol.
On the Windows PC make a new folder somewhere, don't use your desktop but something like C:\Share\MyShare. Right click it and set it up as a share, under permissions add your own account or a new account you made and grant that account full control. Afterwards right click on that folder, properties and under Security tab make sure your account or that new account has full control. This is because there are two permissions levels, first is to the CIFS share, the second is to the folder that share is using.
On the MacOS PC you should be able to access to the share from the Windows PC using the a typical link like smb://<microsoft pc name>/<share name>
https://support.apple.com/en-euro/guide/mac-help/mchlp3015/mac