Yash Sharma

yes you can learn both at the same time python is somehow derived from c++ so syntax in python are very similar to that of c++. Name of the python functions are different but the syntax is same. The sub topics in both the languages are quite same so when you learn a topic in any oneof the two languages and then learning the same topic in the second lanuage turns out to be very easy for you

Python is better,

Python is a multi-dimensional language with ability to do a lot of tasks it is used in developement to make web apps and mobile apps, build API , used to for supervised learning in machines used in deep learning to program neural networks in pytorch,kerans run on python. while java has a limited usability. Java is used just for competitive programming and building low scalable web and  mobile applications. 

The work java does can be done with python but java cannot perform all the things python has the ability to do.

So its better to learn python as python is a future language since all the latest techonologies like the AI (machine learning, deep learning, Data science , Data analytics) needs you to know python programming.

You can use sololearn app wherein you have python courses divided into three sub courses based on complexity and teaching content : beginner,intermediate,advanced which makes it a very good option to learn. You can begin with beginners then intermediate and then advanced. All three python courses are completely free and comes with individual certificates.

or You can take google crash course in python which is part of " Google IT a utomation with python" course i.e. is available on coursera which you can audit and access the course for free (without certification version is free for with certificate you'll have to purchase the course.)

If you want to learn in a personalized manner under a expert mentor and with certification you can find a tutor on urbanpro, you can even approach me i also teach python on urbanpro.