I would say partial mash brewing and/or extract is maybe the best way to start. Porters are extremely forgiving styles and fairly versatile, so you inadvertently chosen a great style of beer to start with! You'll need some kind of fermentation vessel, a kettle of sorts to cook everything, and few extras. Go to your local homebrew store, if applicable, and they should be able to steer you in the right direction. Also, it's probably worth mentioning if you're just starting out, look through John Palmer's "How to Brew". The 1st ed. is available for free online. Cheers!