I am 24 year old, my height is 169cm what should be my ideal weight
This is not only depends on the height it varies on body mass index.According to your height, your ideal weight is 143.37 lb or 65.03 kg. If you wants to calculate your weight on daily basis you can use this Weight Loss Calculator,it shows the appropriate results.
This varies depending on your sex, the ideal weight is generally calculated using Body Mass Index, you can measure your BMI here:
www.betterhealth.vic.gov.au
www.betterhealth.vic.gov.au