How can i load a template I have created in Visual Studio?

Once you've exported your template, copy the entire ZIP file that was created to the folder C:\Users\[User Name]\Documents\Visual Studio 2013\Templates\ProjectTemplates. (You might want to use one of the provided subdirectories to keep your template organized.)

Restart Visual Studio, and then use the search bar in the New Project dialog to help you find the project template you just added.

For the record, it looks like using templates changes with VS2017. Your project template provider will have to publish via a new build mechanic, and it'll be a bit different than just dumping a .zip into a user folder:

Using Project/Item Templates: https://docs.microsoft.com/en-us/visualstudio/extensibility/upgrading-custom-project-and-item-templates-for-visual-studio-2017

Create Project/Item Template: https://docs.microsoft.com/en-us/visualstudio/extensibility/creating-custom-project-and-item-templates