My dell laptop has been stolen and i want to know the mac address of the device to track it. the system is sync with google and windows 10 OS is installed.
Why won't MAC tracking work? Although MAC addresses ought to be unique, there is no convenient way of tracking a MAC address. You would need to have access to lower-level network layers to find out if a device with a specific MAC address is currently connected to a Gateway/Router/etc. Higher Layers such as IP, TCP/UDP don't include references to the MAC address. But only these information (From layers above the Ethernet layer, which uses MAC for addressing) are forwarded for packet routing outside the local network the device is currently in. So only having the MAC address of a device is practically of no use for tracking it if you don't have access to the network it can be connected to.
How to find out your MAC address without the device: If you still have the information on or package of the Laptop, there might be a label with the MAC address written on it. But as said above, this would not be helpful for tracking.
How to still track your device: Your best possible option would be using Googles login history to find out the last login locations (of which it warns you about if there are unreasonable logins from e.g. different countries, unusual invalid login tries).
Unfortunately, MAC addresses are not (usually) routed over the internet.
So unless you have a cached information on your network (internet router, appliance, internal service) or on a paper (original NIC/laptop boxes, ...) you can't find it.
To track your laptop, if you don't have any specific service installed on it for this purpose, you can try to track your connections on online services, like your emails accounts. Some providers allows you to know from where you have an open connection to their service. Should the thief open a web browser that auto-connects to your email account, you might be able to get their IP address.
If you meet legal requirement, you might be able to get ISP to release information on this particular IP address (you probably will have to see the authorities for this)