The theme has three types of templates 2 column, 3 column and 4 column depending on your layout requirement. You can select any one template for the project. Refer the screenshot.
1. How to Add Project?
Here you can add project using this tutorial. Click Here
2. How to create project page?
Go to => WP-Menu => Pages=> Add New
Firstly, Create a page by the name of Project or your chosen name. Select any one-page template like project 2 column, project 3 column and project 4 column then publish the page. Refer the screenshot.