[Monium101]

I'm having a rather difficult time grasping the concept of drawing pairs of entantiomers and pairs of disastereromers, so example how would I go about drawing these components for an amino acid such as leucine. I know first we can draw the diagram firsthand and label each wedge with the atoms and then we label them from 1-4  typically one has the highest priority since the atom there would have a greater atomic number and then go from there but after this point, everything else is a bit confusing. Can someone break it down for me in terms of labeling the structures first and arranging them please? Thanks in advance!

[discodermolide]

Look up the definition of enantiomers and diastereoisomers.
Then search for the Cahn-Ingold-Prelog system of assigning (R) and (S) to the chiral carbon atoms.
From your question I think this is what you are  getting at.

[Monium101]

okay, once I have assigned R and S configurations on the chiral atoms how would I interpret the fact that diastereroisomers are basically stereoisomers that are not entantiomers into drawing them, im still a bit confused.

[discodermolide]

You use the same method:

where the undefined C-OH is a mixture of enantiomers. This compound is a diastereoisomer.
So the two chiral diastereoisomers are:

and


Note here the Smiles engine has labelled the molecules chiral and are not quite the same as I drew them. But it is correct.