How to work with lock layer

How to work with lock layer

You draw and paint on the active layer. You select a layer to make it active. A pencil icon next to a layer's name indicates the active layer. Only one layer can be active at a time. You can edit objects on any visible and unlocked layer. You also can lock layers to protect them from changes and you can hide layers to keep the work area uncluttered.

Step 1

To lock that layer, click in the Lock column to the right of the layer's name

Click it again to unlock the layer.

Then it will show a lock in there