Regarding taking 3 steps for davening:
a)If one ends his davening and wants to take 3 steps back but there is a person still davening behind him but there is a table in between, can one take the 3 steps back because the table seperates the two of us or is this not a valid reason to take the 3 steps back?
b)If one wants to begin davening but the person in front of him or to the side of him already started his tefilla, can he still take 3 forward or do we say that since the other guy started his davening he shouldn’t move at all if he is within 4 amos?
a) A table is not considered a valid separation to permit taking three steps back. Only a valid mechitzah is suitable for this, meaning a partition 10 tefachim tall. A table might be 10 tefachim high (it usually is), but the hole between the table legs would disqualify it as a partition.
b) It is permitted to take the three steps forwards. There is no prohibition on moving, but only on entering the ‘domain’ of somebody in the middle of davening.