When to create seprate templates? does whole project need to make on single index.html file?

i am creating an photoapp were it contain login, signup and many different screens in it, my question is Do i have to create single index.html file for complete project and link it to separate template in template folder?
please guide me as i am new to Ionic. i am loving ionic so much but its hard to achieve some goals

no your app should not be inside the same index.html file and you should use angular-ui for this you can read this article https://blog.nraboy.com/2014/11/using-ui-router-navigate-ionicframework/ which explain everything you need.

Create separate templates if your app contains more than 3 large views. Dont go over the examples from codepen. It is not how it is meant to be on your real full fledged app.

Thank you so much for your help,now i am using “angular-ui” and its working perfectly. for each view i have created separate template.