How do I develop an app by using python. I would also like to create a website, would python help ?

Answer 1

Python frameworks like Django and Flask would help for web development. They are used for developing web applications. But again there are other alternatives for web application development like AngularJS, React or the MEAN stack

Answer 2

Yes you surely can do so with www.kiwi.org . However it's recommended to use Java as Google has many programs, courses and certificates for Android App Development with Java and you can find more number of tools and SDKs