Can I put my views.py file in the project folder of django?
This will work fine. Views can be wherever you want.
You can add the package that is your site (the one that has settings.py in it) to INSTALLED_APPS, and then a models.py in it, management commands, et cetera will also work fine.
Apps are handy when things become big and you want to split them into smaller parts.
I am developing a project using django python server. I have created my project on django and put all my files including views.py in the project folder and I am using it without creating any app and its working fine. 
Is this the right way of doing it (or) I need to create an app instead and put all my files in the project ?