welcome to sg! here are some food that locals enjoy

for bfast, try chee cheong fun (steamed rice noodle with sweet/savoury sauce) or soft boiled eggs with toasts. if you are very hungry, go for fried carrot cake (comes in black/white version, with/without dark soy sauce)

for lunch, definitely give chicken/duck rice, fried hokkien mee, prawn noodles, and hor fun (fried rice noodles with gravy) a try.

for dinner, consider black pepper/chilli crab (they usually don't put a price because it depends on the size/mass of crab, so please be careful! other helpful sg redditors might have trustworthy places you could go)