Wi-Fi and internet service work together, but they are not the same thing. A few simple observations can help show whether the problem affects one device, one part of the home, or the whole connection.
Wi-Fi and internet are not the same thing
Wi-Fi is the wireless connection between a device and the router or mesh system. Internet service is the connection that reaches the router through the provider.
A device can show strong Wi-Fi bars while the internet service is unavailable. Strong bars show that the device can see the local Wi-Fi equipment, not that the provider connection is working.
See whether one device or everything is affected
Check another computer, phone, or tablet on the same Wi-Fi network. When testing a phone, make sure it is using Wi-Fi instead of cellular data.
If one device has the problem, the cause may be on that device. If every device is offline, the modem, router, cabling, power, or provider service may need attention. If only one room is affected, signal coverage may be part of the problem.
Try a few low-risk checks
Save your work, then turn Wi-Fi off and back on for the affected device. Restart that device and try more than one familiar website or app.
Check that the modem, router, or mesh equipment has power and that visible cables are connected. If you restart network equipment, follow the normal instructions from the provider or equipment maker. Do not press a reset button or erase the settings.
Know when the provider may be needed
Use the provider's official app or website from a cellular connection to check for an outage. The provider may need to help when every device is offline, an equipment warning light remains on, or an outside line has a problem.
Local help can still be useful when the provider says service is active but devices will not connect, Wi-Fi is weak in part of the home, or router and mesh settings are confusing.