Still too confused to begin

you should get started with growing a rye sourdough starter first.  After a week, the starter should be able to help you raise a rye loaf.  

Sourdough starters vary in the amount of water in them so we talk often about hydration or the amount of water in them.  One hundred percent hydration means that the weight of the water and the flour is equal.  It is mostly a personal preference so one person's starter uses "a cup or so" and another may use half that amount if the starter is more dough like.  

Yes, you keep a starter growing and use part of it for making bread.  Many of us keep small amounts of starter active (we are so frugal!) and when ready to mix up a dough, take part of it and elaborate or add more water and flour to grow the amount of sourdough starter needed for the recipe -- usually 8 hours or more (overnight) before mixing up the dough.   The sourdough culture is then added to more water and flour and often called a "starter" or "sd" or "rye sour" or some such name.  Any particular recipe?  Link?    

Recipes vary so find one that you can understand.  The greatest thing about TFL is that if you find a recipe here, you can ask questions directly to the person who wrote it up.  If the recipe is from a known author, more than likely there is a discussion on the recipe in the Archives.  We do understand how confusing it can be.  I can also add that for a beginner, diving straight into 100% or even 80% rye loaves (with 20% spelt) can be both challenging and rewarding.  Rye flour does not act like wheat flour and makes a more compact loaf.  Rye dough is lovingly referred to as "paste" acting more like sticky cookie dough.

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