Need advice on taking up a job in Malaysia

Yes I think that salary range is fine. Of course you haven't told us what field of work that is, but certainly you can rent a nice apartment for MYR 3,000 and even lower if you are more out of the city or in an older building, so you should be able to save and live well. If you are living in the centre of the city such as KLCC are, then rents may be higher, but frankly, you can always find less expensive places and there is an oversupply of rental property available so you could also try to negotiate lower prices if you find a place that you like.

The nature of the job will be IT.

As above, I think the salary is fine and you'll get by and save money. Later you'll need to look into primary schools and choose one that you can afford, as schooling not cheap in Malaysia. Also, my son started kindergarten at 1 1/2 years of age and my daughter at 2 years of age. Both went to Montessori school and it was not cheap, although there are always cheaper options starting from simple daycare centers.