How To create a Portfolio page
You can select two layouts for a portfolio page.
First go to your Admin Panel > Pages > Add new, you can put any title, in this case "Portfolio".
On the Template dropdown select one of the Portfolio templates:
If you select Portfolio Masonry you have the option to select how many columns to use.
On the Portfolio Options box you select this:
Also if you have multiple portfolios created, then here you can select which portfolio to display on this page, using this option:
Don't forget to click Publish and that's it, you have a new portfolio item.
Also you can switch to any template layout as many times you want.