Grouping combines several elements into one, so they move, scale, and stay arranged together.
Create a group
Select the elements you want to combine, then either press Cmd/Ctrl + G or open the context menu (the … button) on any of the selected elements and choose Group.
Ungroup
Select the group and press Cmd/Ctrl + Shift + G, or choose Ungroup from its context menu. The elements become individual again.