Hi Michelle,
I'm not getting a clear idea of what your workflow is. Are you zooming to features within your map (geographic space), or are you zooming into a section of the map frame (page space).
You can set a map frame constraint to manage the extent of the map - see Map frame constraints—Layouts | ArcGIS Desktop .
You can also lock elements so that you don't accidentally move them when selecting other elements on the layout page.
From the help topic Layouts in ArcGIS Pro—Layouts | ArcGIS Desktop:
"Once added to a layout, elements can be selected, moved, and resized on the layout to achieve the desired look and feel. This behavior can be turned off by locking an element, preventing selection, moving, or resizing interactively on the layout. Switch between locked and unlocked views by clicking the Lock button next to the element in the Contents pane."
Even though you lock an element and cannot interactively select the element, you can still select the element from the Contents pane if you want to open the properties of that element.
Hope this helps,
Tom