Creepage Analysis can be found in the "Analysis" tab. The following picture shows the main view after clicking the "Creepage Analysis" button. As you can see, there are three different tabs.

1. Net to Net
2. Net Group to Net Group
3. To Outline

1. Net to Net creepage analysis is used to detect creepage issues between two single nets.
2. Net Group to Net Group creepage analysis has to be used to detect issues between any net of the first group to any net of the second group (Note: You have to create Net Groups first. To create Net Groups use the button of the following image. Creating net groups can be found in "Net Groups", shown below)
3. There is also an option to detect issues between a single net, or any net of a group to the board outline of the PCB