It is about 18 inches tall. Dwarf banana trees are great tropical foliage. They do best in full sun. The larger the container, the less you have to water. I would opt for at least a three gallon pot if possible.
Banana trees are heavy feeders and like organic matter.
Any commercial potting soil would work, but I would use half potting soil and half organic matter. Organic matter can come from humus, compost, etc. Banana trees are not winter hardy, so it will need to be moved inside for the winter. We bought a banana tree last year. It grew wonderfully this summer.