A Hotspot is used to connect your devices, (laptops, iPads, etc), to a wifi connection that is transmitted by your phone. To use your phone as a hotspot you need to turn that feature on in the settings of the phone. Most phones have the option to turn on a “Personal Hotspot” within the first page of your Settings feature.
Once that is turned on you will need to make sure your devices can “see” the hotspot. To do so you may need to turn off and then on again the wifi on each device so that it will search for new connections. You may also have to manage your wireless connections by removing everyone it finds which allows the device to search for new locations to connect to. At this point it is critical the devices at least “see” the connection even it cannot connect.
If you are still unable to connect to the hotspot, but can “see” it then the issue can be resolved by disconnecting all devices currently connected, (if there are any), and then shutting off the phone completely for a couple minutes. Restart the phone and try to connect again. Should now work.