Hello @Tina Mills
There are many ways companies can track the activity. If you are using your personal laptop, but you are not using company tools or company VPN surely your employer cannot monitor your personal internet connection or computer.
Other cases, when they can monitor, is if you are using a corporate VPN to connect, as that network connection uses your company's gateways and traffic will surely be monitored.
Other possibility is that if you have enrolled your Windows computer by using you Work or School account to access applications, as this will open the possibility for your employer to add policies and surveillance software to protect the network/applications/data.
Hope this helps with your query,
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