Porter, Apporter, Emporter
1. Porter (for things)
To carry a box, a table, luggage…
To take: You are going to take the letter to the post office: tu vas porter la lettre à la poste. (here you can also say apporter) (to deliver), the meaning is: tu prends la lettre pour la mettre à la poste
To wear: porter un manteau = to wear a coat
2. Apporter (for things)
Apporter = porter à
There is a notion of movement, with a focus on the arrival.
Apporte moi le livre: bring the book to me. The meaning is ‘take the book and give it to me’ = prends le livre et donne-le moi.
3. Emporter (for things)
There is a notion of movement with a focus on the departure.
To take (away)
J’emporte un manteau avec moi: I take a coat with me.
You can also use “prendre” (to take): je prends un manteau avec moi.