This tutorial will help you to how create a transparent background in Photoshop; the file needs to have a transparent layer, which achieved in two ways.
1. Create a New Transparent File
From the menu select File> New a new window open at the bottom under the contents you will find a transparent tab you need to check it. After that add your image into a new layer, it will automatically happened if you copy and paste the image in Photoshop.
2. Add a new Transparent Layer
If you want to add a new layer then you can add it by selecting Layer> New> layer from the menu, this new layer will be added above the currently selected layer. Drag this new layer below the image layer.
You can use any method but after that you must be having two layers, one with image and second with transparent background which will below to the image layer.
3. Make Transparent Area.
Select a layer of an image, after that select magic wand or lasso tool to select an area which you want to be transparent.
Hit the delete button to delete that area, the selected area will be deleted and you will be having an image with transparent background.
Now you have an option to save it as a Tiff, JPG, Bitmap, PSD etc. it’s your choice