What is the model of your WIFI router? The address may vary according to the brand of your router. . I have bought Netgear AC3200 - R8000 Nighthawk X6 Tri-Band (https://themybuy.com/best-wireless-routers/).
It has two default adresses - 192.168.1.1 or 192.168.0.1.
And it comes with a Smart Configuration Wizard about how to install it properly:
Launch a web browser from a computer or mobile device that is connected to your router’s network.
Enter http://www.routerlogin.net or http://www.routerlogin.com.
Note: You can also enter your router’s default IP address (192.168.1.1 or 192.168.0.1).
Enter your user name and password.
The user name is admin and the default password is password. Entries are case-sensitive.
If the default username and password are not working, try other passwords that you might have changed to. Otherwise, a factory reset is needed to restore the router to factory defaults. To perform a factory reset, see How do I perform a factory reset on my NETGEAR router?.
The Basic Settings page displays.
In the upper-left corner of the screen, click Setup Wizard.
The Setup Wizard screen displays.
The Setup Wizard detects your Internet connection.
The router saves your settings and connects to the Internet.
(Optional) To check if you are connected to the Internet, select Router Status under Maintenance.
Check the same setting tips for your router. I think that they may be similar.