Definitely learn one language at a time, just like learning Portuguese and Spanish they may sound alike in a way, but have a lot that is different. The same goes for Java and Java Script. I am in the process of learning Java Script. I use codecademy and ask questions on its forum and even give answers as well. Persistence with purpose leads to success. Be patient with your self
Tutorials Point is also the best place to refer, learn from codecademy and refer from Tutorials Point!
Kk thank u