How Do I Lock a Background in Illustrator?

To lock objects, click the edit column button (to the right of the eye icon) in the Layers panel for the object or layer you want to lock. Drag across multiple edit column buttons to lock multiple items. Alternatively, select the objects you want to lock, and then choose Object > Lock > Selection.

How do I lock an image in Illustrator?

To lock selected artwork, choose Object > Lock > Selection.

How do you lock dimensions in Illustrator?

To constrain the object to its original width, hold down Shift. To shear along the object’s horizontal axis, drag anywhere in the document window in a left or right direction. To constrain the object to its original height, hold down Shift.