How to Block Access From All Devices

Question

How do you block all devices from accessing your laptop? I think someone is connecting to my laptop. I disconnected my modem then I checked Windows Update on my laptop. It had that it was up to date and the last time it checked was when I logged in. How is this possible if my laptop isn't connected to the internet and wasn't even turned on. I have a smart TV that's connected via Chromecast. I have windows 10 home edition with the following settings.

Network $ Internet/Airplane mode/On
Network $ Internet/Wifi/Off
Network $ Internet/VPN/Allow VPN over metered network/Off
Network $ Internet/VPN/Allow VPN while roaming/Off
Network $ Internet/Status/Network troubleshooter/Change advanced sharing settings/(eveything under Private and Guest or Public (current profile) is set to Off)
Phone/(not set up)
Privacy/App permissions/access for this device is off on all apps
Privacy/App permissions/Allow apps to access is off on all apps

Device Manager settings:
Dell Wireless 1705 Bluetooth/disabled

Answer 1

This is my personal laptop. I have Norton AntiVirus. Under Windows Defender Firewall "Guest or public networks" is connected and managed by Norton AntiVirus. I found this article to change the trust level of your network that's enabled by default (ARRRGH!). v9802264