Should i get a MacBook Pro or Air?

[Gracie]

I'm in the 10th grade and I use Microsoft Word alot. I also would need to use Microsoft PowerPoint. I don't know for sure, but I think Macs and Apple devices don't have/use Mocrosoft...? I really liked the MacBook Air, because of its lightness and portability. But the MacBook Pro seems so much better when it comes to storage and visual quality. So I'm very confused. I like to import alot of my photos and videos from my iPhone into my laptop, make videos and taking pictures on my laptop, watch YouTube, Facebook, Twitter, listen to muisic, and I also would like to start watching movies on my laptop. So I'm going to be using it for many things. I'm planning to get a 13 inch, but maybe a 15 inch? I think a larger screen would be better for videos and pictures, but I don't know if it is worth the extra money and weight. I still want it to be easily taken and light so that I could take it around the house or library. I think if it came down to it I would pick the MacBook Pro...? ^ I hope this gives an idea of what I should get. I want to know for sure what size and model to get! thanks. X oh also what's. the difference between like retina and um non-retina?lol I don't know all he tehnicl terms.
Also what would you recommend as a laptop bag? Or case? Should I get invisible shield? I thought about the Timbuktu messenger bags, but it's a little too pricey for me, especially since I'm only in the 10th grade. & I don't want a case too bulky, but I also want to protect it from damage. I want a bag or backpack to be very durable and to withstand the weight of the laptop and possible some notebooks thanks!x