You need to trial & error for formula milk cos it depends on your baby's liking but the non expensive one are Dulac, NatureOne, Fairprice. Diaper can get Pet-Pet or those Ntuc brand.
I use this for my NB baby Platinum Huggies NB Frisolac gold 400g( try first if ok than can buy 900g)
my LO drink frisolac gold since NB till now 5mo and she using huggies gold.
Nestle, then Similar for baby formula, for diapers Huggies and mamypoko
You can try Nature One it cost $30 and Drypers wee wee dry dipers
natureone, dumex dulac n rascal+friends, drypers, pampers
Mamil gold. Mamypoko extra dry and huggies gold
Dumex dugro & huggies 👍🏼
for us, mamil & drypers 💕
drypers touch diaper!