Convertible vs infant car seat.

I’m due in April with our second baby but this baby will probably be born in March as I’m high risk and will be induced early. We got a really nice convertible car seat that goes from 5 pounds to 65 pounds and rear facing to forward facing. Do you think we NEED to get an infant car seat with a handle that goes in and out of the car? We are moving in March 2020 so I’m trying to keep our larger purchases to a minimum. If you think we do need one what brand and model do you recommend?