Is Ganga a west flowing river?

No, Ganga is not a west flowing river. It rises in the Gangotri glacier near Gaumukh (3,900 m) in the Uttarkashi district of Uttarakhand. It flows eastwards and enters the plains at Haridwar. From here, it flows first to the south, then to the south-east and east before splitting into two distributaries, namely the Bhagirathi and the Padma. The river finally discharges itself into the Bay of Bengal near Sagar Island.

Further Reading:

• What are the Parts of a River Called?
• The Major Indian River Systems