A. You cannot parry or block someone with a heavier weight class than you, it will destroy your arm. B. It doesn't matter how many moves you know in boxing if your opponent doesnt know how to fight therefore making these moves useless without actual mentorship from a trainer. C. None of this matters if you have poor footwork, thats the most important thing in a fight.
I've fought someone who doesn't know how to fight, rolls and step backs work really well since a lot if people just seing their arms. You can definitely block a heavier weightclass depending on how far apart, they have to have lots of weight for proper blocks to not work.
