Select the path or anchor point using the Direct Selection tool.
Learn how to stop the Pen tool from automatically switching to the Add or Delete Anchor Point tool when hovering over a selected path.
Using Pen tool controls
Press Shift as you hover the Pen tool over the selected path or an anchor point to temporarily turn off the Add Anchor Point or Delete Anchor Point tool.
Select the desired location on the selected path to start a new path directly. To avoid constraining the path while using the Pen tool with the Shift key, release the Shift key before releasing the mouse button.
Using Illustrator preferences
Select Edit > Preferences > General (Windows) or Illustrator > Settings > General (macOS).
Select Disable Auto Add/Delete, and then select OK.