Question about whether people with nut allergies can eat local food in Singapore: probably not, except at very specialized restaurants (nut allergies are almost unheard of there)
According this study, peanut allergy prevalence in Singapore is only 0.1-0.3%, compared to >1.40% elsewhere: https://pmc.ncbi.nlm.nih.gov/articles/PMC7016321/
https://www.reddit.com/r/askSingapore/comments/1m62oiy/dining_in_singapore_with_peanut_allergy/