Belgium does have national health insurance, which your employer must provide for you. I think the doctor that was discussing this with me said there are now some co-payments for some things.

Try to get as much covered by your employer as possible, including not only a housing allowance but some help in getting settled and getting everything organized. Compared to India (or even the US) everything will seem monstrously expensive. Since you are only going for 18 months, and your child is so young, school won't be so much of an issue for you.

Also, from what I remember from my travel in India, having servants is usual for people with professinal jobs, and that's not the norm in Europe. I mention this because I have met many people who are stunned to discover that the richer the country you come from, the more likely it is that you will do all your own housework.