How to add blue sky and white clouds with ps

Step 1: Open the prepared picture in Photoshop (as shown below).

Step 2: Set the background color to white, and use the cutting tool to enlarge the background (as shown in the figure below).

Step 3: Baidu downloads the blue sky and white clouds material layer and puts it inside (as shown in the figure below).

Step 4: Put the blue sky in a suitable position, add a mask tool and pull a black-and-white gradient (as shown below).

Step 5: When using the brush tool, select black and clean the edges (as shown in the figure below)?