Newborns are easier to bring out in my opinion, cause they are still quite sleepy and don't need to be entertained as much as an older baby. I'd say bring a compact carrier like Konny. You'd likely need to get a car seat capsule for grab rides, and a stroller that you can attach the capsule on since baby can continue to sleep/ rest in it after the ride. Bring the usual - wipes, diapers, changing mat, feeds / nursing cover. It gets better with more practise. All the best!
I bought my nb out put her in my konny got stroller tgt too. inform the grab driver I have a nb see if they accept. usually I will call gojek as they do not have option of needing a carseat
some details:https://community.theasianparent.com/q/i-know-safe-start-bringing-2-months-old-out-evening-walks/1232272