“Problem seems how much fuel is required to maintain that acceleration that long”
With our current understanding of physics the best way to get to the stars would be an array of solar powered lasers on the moon. They would be focused on light sails of a space craft. The craft could then steadily accelerate to a significant portion of light speed.
Eventually, you’ll need to slow down and stop.
Light sails are interesting, but precision is presumed problematic.