My parents are only covered by NTUC assist rider with no life insurance/CI plans. As a fresh grad earning more than $3000, I'm not sure if i should get CI and/or life insurance for my parents. What do you think?

A Critical Illness plan is to cover the loss of income due to the inability to work due to illnesses. Majority (possibly all) of his hospital bills will be taken by the NTUC Shield Plan.

Your father needs to understand this first. Because even if you "buy for him", he might think you're wasting money.

If he is still generating income for the family or his retirement for a number of years, you may want to get him a Term CI plan to also manage affordability due to his smoking status.

If budget is the ultimate concern, a term till retirement to protect the income he would have created, would be sufficient.

The rule of thumb is to go for about 3-5 X Annual Income in CI Cover.