I have a macbook pro from 2013 and I need to buy its original charger, can you help me with some information on how to get one?

For 13 inch MacBook Pro 2013: Apple 60W MagSafe 2 Power Adapter - Apple

For 15 inch MacBook Pro 2013: Apple 85W MagSafe 2 Power Adapter - Apple

Also ee the following from Identify your Mac power adapter - Apple Support

85W MagSafe Power Adapter with MagSafe 2 style connector

• 15-inch MacBook Pro models introduced in 2012 through 2015

60W MagSafe Power Adapter with MagSafe 2 style connector

• 13-inch MacBook Pro models introduced in 2012 through 2015

You can freely use a power adapter (with correct MagSafe connector) that has a HIGHER charging capability that the originally issued model. Nothing will be damaged in any way.

If you change from standard, be sure to check carefully for the correct MagSafe version -- there are now THREE different ones.