Hi Ompal,
Personally I would advise you to focus on ECS. Campus EXOS Switching & Routing currently contains almost everything from ECNA EXOS Fundamentals. Some changes are coming but it is not yet known what will they be like eventually. It's up to a trainer to put accents differently in those classes (whether you have general knowledge about networks or not - but in this case you could see free of charge 'Introduction to Networking' online training on the training portal).
Hope that helps,
Tomasz