Hello @ArjunP ,
We’re so excited that you started course 1 
These four courses are meant to be taken in sequence because the concepts and assignments in later courses build on top of the concepts learned in earlier courses. So, we encourage you to complete course 1 before starting course 2, and so on.
When you enroll in a course, Coursera automatically sets the deadline for assignments based on the current date. Don’t worry, when you get to the later courses, you can just reset the deadlines.
Hope this helps!
Jess