Blend on low until thick and smooth, stop to scrape down sides along the way.
The optional ingredients depend on what you choose to add. If you use protein powder that is sweetened, then you may not need any dates. If you use vanilla yogurt that is sweetened you also may not need any dates.
You can add the almond butter for extra protein and healthy fat.
I like to freeze milk in ice cube trays to use with smoothies because it makes it much creamier than using ice.
If you forget to freeze your banana, this will still work but you may need more ice. It also won't be as creamy smooth.
The nutrition information will change a lot depending on the brands you use for each ingredient. You should calculate them yourself for accuracy.