Workflow loop through the users in a SP permission group

You don’t need to find the people in a group you can just assign a task to the SharePoint group.

In designer add user task and step through the wizard, when you get to the participants step use search but change it from people to groups. Search for your SharePoint group by name. You will see both SharePoint groups and Add groups used in SharePoint. Drag this group to participants and select all at once.

Here is what I think is the tricky part. After you finish the task. You need to modify the outcome rules. As you hover over your task you will see icons appear. You want to select outcomes (looks like a pyramid of connected boxes).

For my example I just have an outcome call Complete but you will have one for every outcome you specified. Select the check box next to the outcome and select edit. The default is "One" participant selected the ‘Complete". If you want each user to have to complete the task then change "One" to "All" or if you want a specific number to complete like 3. Clock OK and do this for all outcomes if desired,

I hope this helps