Help with regards to Dependent Visa for Germany

Hello and greeting to everyone on this forum. I have been following this form for the past few weeks and have gained from a lot of useful suggestions. Now that I finally have an appointment date with the German Consulate in Mumbai, I am posting some of the questions I had. I would really appreciate if the experts here or people with similar experiences could guide me.
I have a guaranteed job offer from a company in Hamburg. They have offered around 90000 Euros salary. I already have an appointment in first week of August at the German Consulate in Mumbai to apply for National Visa. the question I had was regarding my young kids. Can i apply for them at the same time as me or do I need a separate appointment for them. Also under Dependent category, do I apply under Family Re-union Visa or is there any other category I can apply under. Ideally I would like to take my kids along with me when i fly to Germany.
I have been trying to clear my doubts with VFS (they are the ones who take the appointments on behalf of the consulate), but they have not been very helpful. I have also written an email to the consulate but haven't had a reply.
I would be grateful if someone could guide me or share some of their experiences.