There are multiple ways of selecting layers in the workspace. Layers can either be selected from Canvas or from the Layers & Components Panel.

On Canvas

You can select multiple layers and apply common operations at once. You can click and drag the selection area with your pointer to select layers inside that selection area

Alternatively, you can also press the shift key and then click on multiple layers to select them.

To select a nested layer, you can double click on the parent layer and then navigate through nested layer at the next level by double clicking again.

To select the inner-most nested layer directly, you can press the key and then select the layer.

Through Layers & Components Panel

You can also select layers from the Layers & Components panel.

You can directly click on the layer name on the panel to select it.

To select multiple layers you can press the key and select each layer one by one.

To select multiple layers at once, you can select a layer, press the shift key and then select the final layer. All the layers between the first and the last layer selected in the panel will be selected.