Hello, PopeJulius,
The Lumia 535 is limited to 3G connection only as a maximum for mobile data. 3G should bring you a minimum of 144kbps, but most of the time it should be within 400kbps to 4Mbps depending on your location and your mobile service provider.
Should you wish higher internet speeds, you may want to connect to Wi-Fi that is faster than the rated speeds of 3G instead.