Now I am studying Andrew NG course a machine learning course. So is it a good starting point in this field or should I do another thing?

It is really a good starting point in this field. The course is well constructed, has minimum mathematics and every topic has few examples with it.

I went through few online courses and finally selected this one to complete based on follwoing reasons -

1. Depth of content - Other courses are just describing ML topics and showing how to use python or other libraries to use various algorithms. But This course discusses mathematics and reasoning about various algorithms.
2. Programming Assignment - One of the coolest (and thoughest) part of the course. Very well structured and challange you to apply your learning
3. Teacher - Prof Andrew is very well known in ML/AI field. He is like celebrity in this domain who were part of Google Brain, Baidu AI and just started one more company with Foxconn.
4. Stanford University affiliation - Last but not least, You will get the certificate with the stamp from one of the respected university 

You may go through the data science skills to completely understand the machine learning.

Its good because we learned step by step.basic and its nescesaryto add some technic or strategy which we have mass production and quality for delivering on time.

Having done this course, I will also recommend that you study "Machine Learning with R" second edition by Brett Lantz and also "An Intro to Statistical Learning with applications in R" by Gareth James, Trevor Hastie, Rob Tibshirani. 

They have working datasets and you will have a greater learning by working through those datasets.

Go Python online study below is link 

https://www.guru99.com/learning-python-strings-replace-join-split-reverse.html

Yes however it is highly technical and less applicable than other courses:

1. http://www.datasciencecentral.com/profiles/blogs/neural-networks-for-machine-learning : Great blog with lots of links to websites. 
2. Free course on Machine Learning: Andrew NG is the Chief Scientist at Baidu: https://www.coursera.org/learn/machine-learning If you can’t access the videos through here: https://www.youtube.com/watch?v=UzxYlbK2c7E&list=PLJ_CMbwA6bT-n1W0mgOlYwccZ-j6gBXqE
3. https://www.r-bloggers.com/in-depth-introduction-to-machine-learning-in-15-hours-of-expert-videos/ Great course with R tutorials on Machine Learning techniques from experts Professors
4. https://www.udemy.com/machinelearning/ - Udemy do a great course with R & Python tutorials. 
5. Machine Learning Mind Map for Python: http://scikit-learn.org/stable/_static/ml_map.png Great for when you don’t know which Machine Learning algorithm to use in different scenarios.
6. https://www.kaggle.com/ Great place to apply your new Machine Learning knowledge and learn new techniques through other contestants’ approaches.
7. From the latest Google Cloud Conference, https://www.youtube.com/watch?v=w1xNTLH1zlA&list=PLIivdWyY5sqI8RuUibiH8sMb1ExIw0lAR&index=79 

Andrew NG course is definately a top notch, but to Start with, I would recommend to go step by step.

Start with basic Statistical learnings, then Statistical Modeling and then come to Andrew NG's Machine Learning course.

Try Online learning platforms like, coursera , udemy , edX etc..,