Answer 1

You have almost finished your Javascript tutorial. Looks like you're already learning it.
Please use this forum only for *specific* questions!
https://www.sololearn.com/discuss/1316935/?ref=app

Answer 2

No one is stopping you
Jump right in!
https://www.sololearn.com/Course/JavaScript/?ref=app

Answer 3

....just complete Solo learn tutorial and then go for more advanced level in other sites....

Answer 4

Redo you tutorials from the start and after each tutorials make a code related to it (practice it.). Go to next tutorial and make a new project which is combination of previous one.