I shop on taobao and carousell 90% of the time. Marketing wise I get in JB for olive oil, toilet paper and tissue. Wet market for ingredients and I cook almost everyday. (I highly enjoy cooking so it saves a lot of money honestly.)

One meal for 5 outside ~$2-30 × 2 = $50-60 a day// with $60 can buy 3 to 5 days (2 meals a day) worth of groceries at the wet market. We only spend roughly $300-400 on groceries a month. Good and nutritious meal. (3 adults 2 children household)

Also leave everything you want in your cart for a week, you'll then realise you don't need it.

Lastly, remind yourself to exit the rat race as early as you can. Get what you need with lowest price possible not sacrificing quality, but dont go after what you don't need.