Both devices are most likely on the same subnet if they are both connected to Ethernet on the same router, but you would have to check & compare their IP addresses and check your router's network configuration.
You need to use the "mount" command with the "-t cifs" option which signifies an "SMB" share. You can use "man mount" and "man mount.cifs" to learn about the various options for "mount" with the latter being for the specific SMB options.
man mount
man mount.cifs
A sample of the most basic SMB mount command is in the format of:
SMB server with DNS name:
sudo mount -t cifs //<smb-server-dns-name>.local/<smb-shared-folder> <local-mount-point> -o user=<macos-smb-user>
sudo mount -t cifs //<smb-server-dns-name>.local/<smb-shared-folder> <local-mount-point> -o username=<macos-smb-user>
SMB server using IP address:
sudo mount -t cifs //<smb-server-IP-address>.local/<smb-shared-folder> <local-mount-point> -o user=<macos-smb-user>
Replace "<smb-server-dns-name>" or "smb-server-IP-address>" with the SMB server's DNS name or IP address. I'm assuming you don't have a formal public DNS name for the Mac hence the ".local" after the DNS name to represent the local subnet. Using an IP address is safest until you confirm you can mount the share.
Replace "<smb-shared-folder>" with the actual folder being shared on the Mac. I'm not sure how macOS configures the SMB shares so I'm not certain how much of the path is required.
Replace "<local-mount-point> with your desired mount point for the share.
Replace "<macos-smb-user>" with a macOS user name/account with permission to the SMB share.
For example if your Mac's DNS name is "hwtechs-mac.local", the shared folder is "myshare", and the macOS user account name associated with the SMB share is "hwtech" you can use the following command:
sudo mount -t cifs //hwtechs-mac.local/myshare /mnt -o user=hwtech
I haven't tried using Linux to mount a macOS SMB share in a while so I'm not sure if you will need to apply any other options to the mount command. I know that other options are sometimes required when mounting Windows SMB shares.
To use the "verbose" option to hopefully get more details on any mounting errors you would need to add the "--verbose" option after the mountpoint, but before the "-o " options like:
sudo mount -t cifs //hwtechs-mac.local/myshare /mnt --verbose -o user=hwtech
Don't forget to check your Sharing permissions on the Mac. The macOS Sharing section may provide some information such as the DNS name and IP address plus the path for the SMB share. I'm guessing macOS doesn't provide any "Domain" for the SMB share so using the basic command I have listed here will likely work. I also cannot connect to my Linux SMB share from the GUI most likely due to the forced "Domain" option. If you search online for using Linux to mount SMB shares you will get other examples (mostly for connecting to a Windows share, but it may still be relevant since it is very hard to find examples for connecting to a macOS SMB share).