Adobe Acrobat Pro provide multiple of facilities for you such as join / combine two or more PDF document to know how to do that follow the below steps:

  1. Open Adobe Acrobat Pro 
  2. Go to Main Menu of Adobe Acrobat Pro Go to File >> Create >> Combine files into a Single PDF 

3. Will pop up to you combine Files window as below image 
4. Click over Add Files button and Select the files you would like to Combine within Single PDF

 5. Click Over “Combine Files  to Combine the files into a single PDF 
6. Just don’t forget to Save the document which you combine .