Definitely not - that plant doesn't even have any viable leaves yet. It needs leaves to make food for itself to grow. Right now, it needs soil, water, nutrients and sunlight.
If you can grow it until it has about a dozen big shiny, healthy dark green leaves, then maybe you can indulge your urge to prune, and pinch out the terminal growths - maybe by the fall? But I wouldn't. The more leaves that plant has to collect light, the better it will grow through your rainy, gloomy winter months.
You definitely will need to keep it indoors in winter, but it will do fine as a potted plant outside in the summer. Just don't forget to water and feed it. As soon as the night temperatures are above about 50, you can take it outside. Then in the fall when the nights start getting below 50 again, it's time to bring it in.
These are tropical fruit trees. It will die if you let it get too cold for too long. To grow a tropical tree in a place that is not tropical, you have to try to give it as close to its 'natural' environment as possible. Here, avocados grow into 30ft. trees in the full, blazing Florida sun. (they grow great in California too).