Hey Shwen,
We understand you're not sure if the Apple MagSafe Charger you purchased is genuine or not. The best way to know for certain is by looking at where it was purchased from. If it wasn't purchased from an Apple Store or Apple Authorized Reseller, there's no way to guarantee it's a genuine Apple product or not. You can purchase a new product with confidence that it's genuine by always ensuring you purchase from one of the two.
For help locating an Apple Store or Apple Authorized Reseller in your area, visit: Find Locations - Apple
Once at the link, you can change the country/region in the bottom-right hand corner of the page.
We hope this helps out.
Take care!