Converting our body to data? Well that's a very good question, you're looking at beyond trillions of gigs of information. You would also need to ensure that every single molecule is correctly translated into data. Now, if you wanted to abandon the body and simply convert the brain to data, please keep in mind just how insanely complex the human mind is. Even the tiniest error, and the mind that's uploaded may be completely damaged. Memories erased, schizophrenic, depressed, etc. And that's just for starters. It's a beautiful dream, but right now that's all it is, a dream. The idea of digitizing a human to that extent is, at this time and current level of technology, completely impossible. However, in the future, it could be possible once we are able to 100% map out, translate, and understand the human brain in every single detail. But for now, it's simply beyond our capabilities.
When it comes to humans going into space, at this time, we'll have to physically go. The likelihood of us coming up with a way to create a form of artificial gravity, that is to simulate the g-forces our body feels on earth so we can survive in areas with lower gravity, is currently underway with results that are quite extraordinary. Now, as for nutrition in space, there has been a theory that we could, using technology such as CRISPR, alter the human genome and add the DNA of plants within our biology allowing humans to photosynthesize and for our bodies to, in some small amount, produce its own food. This would be a significant feat if it could be accomplished. This would mean far less food resources needed for the individual, just water. However, this would lead to a great many ethical dilemmas as far as genetically engineering a new type of human, so to speak. But that is a discussion for another time.