Recommend Sunscreen For Body And Face

What do you suggest the best sunscreen for my face and body? I've always been under the sun as I walk to home from school. How should I lose my weight? I've flabby arms and thighs. And how can I reduce and remove my acne and the scars effectively? Also how can I whiten my skin tone? I'm a malay and my skin tone is brown, not too dark and not too light, plus my face tone and body tone is different due to the amount of sunlight exposure :( My face tone is darker.. Please help me, thank you :)