Editorial is basically the ideal approach to solve the problem, as per problem setter/tester or editorialist. (Note that there may be other approaches to solve the problem.
Well, Suppose you are looking for editorial of problem ABC, Open link discuss.codechef.com/problems/ABC.
If the official editorial has been posted, it will open.
Else you can use discuss search feature. Just type problem name/problem code, You’ll see all discussions, question and editorials regarding that problem.
PS:It is not necessary that each and every problem has editorial available.
You can use codechef ide to debug your code, make submissions to contest and well as for practice.
There are three monthly contest, One long challenge of 10 days (going one now), One 2.5 hour Cook off (Second last Sunday of every month in ACM-ICPC format) and 3 hour Lunchtime (Last saturday of every month in IOI format).
You would like to practice problems at https://www.codechef.com/problems/school or easy section.
Be sure to read Code of Conduct