Welcome to garden.org . My goodness, that's a nice big Amaryllis. It should certainly bloom next year.
If you could let us know your location, it would help to answer this question because IF you are living on an "island in the sun" you can just put it outside and let it do it's thing.
Here in Florida, (and in much of the South) Amaryllis are our spring flowering bulbs in the garden. They keep their leaves all year round, and flower faithfully for a few weeks in the springtime. Btw, they grow in full sun here, so perhaps yours would benefit from more light? It's a very dark green which sometimes indicates it needs more. On the windowsill rather than in between the windows, maybe?
If you're keeping it indoors, then through the winter's cool weather and low light, let it cool off at nights and ease back on watering it - maybe just a little every couple of weeks. Then when it starts pushing out some new leaves in the middle, pick up watering it fairly generously. I give mine about a teaspoonful of timed-release fertilizer after the blooms are done and I've cut off the bloom stem.
