Step 1:- Cut seashore part from any picture.
Step 2:- pick a mountain image cut it and place it Properly.
Step 3:- Make a new layer and paint the mountain with same color of mountain, Paint with 80% opacity to make it look far. (If necessary make it little blur with blur tool)
Step 4:- Take another mountain image and repeat previous step with 50% opacity.
Step 5:- Create it’s water reflation by painting same colors or duplicate layer and flip it vertically and reduce opacity to look realistic.
Step 6:- Again take a mountain image and put that mountain in front and mask the mountain to match with ground.
Step 7:- Take a boat and make it little Bright by painting white color on it’s duplicate layer and make layer opacity to 5%
Step 8:- Make Boat shadow by using brush tool and play with opacity to make it look real.
Step 9:- Take a sky image and place it behind all layers.
Step 10:- Take 1 more a cloudy sky image place it properly and reduce 70% opacity (depends)
Step 11:- Place a png image of birds and blend it with softlight.
Step 12:- Make an black & white adjustment layer over all layers make it’s opacity to 50%.
Step 13:- Take a color balance adjustment layer and change colors as shown in image below. (or you can make your own color there to your project)
And this is how you can create a simple matte paint in Photoshop