Much depends upon the model and the programmed configuration. Typically, you can. However, you must access the documentation for your router to gain this information.
If the access point is acting as a DHCP server, it will typically assign its Web access address your default gateway.
At the command prompt, type
This will give the settings for your network card, to include your default gateway IP address (something like 188.8.131.52 would not be unusual).
The default gateway address can be copied directly to your Web browser and you should be prompted for a user name and password. These may be provided on the side or back of the device.