Start with checking if another device can access the wifi connection that you want to access (such as a tablet or smartphone). You may need to reboot the router and the modem to get it working. If it does not, contact your ISP.
If it is working, delete the wifi profile in Windows, and reconfigure the network. Also, on some laptops, the wifi can get turned off via hard switch, or a keyboard function. Look for the wifi logo and make sure it is on.
Make sure the wifi has a driver as well.
If none of this works, get a USB wifi adapter, which will have its own software, and simply bypass the issue.