Within Installed Packages, there is a configuration option for addition setup steps
You can add custom fields to activities. As these fields are not always required and custom fields for activities have limitations, you can select the fields you need
•Call Hold Time - records per call how many seconds the call was in hold state
•Call Ring Time - records per call how many seconds the call was in ring state
•Call Duration (total) - summary of Call Hold Time + Call Ring Time + Call duration (time spent on the active call)
Tick the field you want to add and click on the button: Create Fields.
Then add the fields on the Task Page Layout