I've been always servicing my car honda civic in official honda service center, but since I'm out of warranty recently, thinking to change it outside to save cost. A few question to ask almighty /k

1)I don't vroom vroom my car, what type of oil I need to buy? What brand? And how much?
If you dont vroom, you can use
0-20 and 0-30 if your car is new. If not use 5-30 semi.. 10-30 honda oil is mineral.

2)Any good place to buy engine oil(Lazada/shopee?) or straight get from the workshop guy?
If shopee can try dongjintrading or tulensakti. Confirm ori.

3)how much is the normal fee I have to pay?
Normal oil change my area is RM10 for small cars. But I think KL around 20 above.