Is it possible to use Python backend and a Android/Native application as Front end
Yes, it is possible.
For example, you can use Python as backend (server), with some exposed HTTP "interface", then make an Android application that communicates with these Python backend with HTTP request / response.
Or, if you are making a serverless application, you can make this Python backend as a .so library or using SL4A then call them in your Android application.
I am handling my second year project which includes some machine learning backend along with a Mobile application front end.In simple terms i am creating
a androing/react native application which would take an input from the user and prosses in a backend development which includes python for some machine learning.
My question is, is it possible  to connect these 2 together. I have gone through some stuff altho i am not very clear on how to create a connection on this. 
Also some opinions on either i should go with android or react native or any other language to go on python or not would be very  useful. 
Thank you