Images link

https://unsplash.com/
http://thenuschool.com/free-stock-photos-websites-awesome-list/

Photoshop tips

Layer detection:

1. check the auto-selection box and
2. select layer option from drop-drown

Set background on a layer:

1. Select the layer
2. Right click on the right side of the layer and click on  'convert to smart object'
3. Click on the layer thumbnail icon
4. Set the background

Photo size

Passport size: Width1.5″× Height 1.9″ × Resolution-300

Stamp Size: Width.8″× Height 1″ × Resolution-300

4R Size: Width 4″× Height 6″ × Resolution-300

Photoshop tutorials

Photoshop tools: https://helpx.adobe.com/photoshop/using/tools.html
How to create mock up:
https://www.youtube.com/results?search_query=website+template+photoshop+tutorial+cc

Smart Object Mockup Photoshop Tutorial https://www.youtube.com/watch?v=6VCHinV708s