Some of what you write is in the form of a logical fallacy called [begging the question](rationalwiki.org/wiki/Circular_reasoning): you are assuming something is true instead of proving first that this is the case.

and we as twin souls in a human body cannot do anything about it.

You see? You are assuming twins are a soul in two bodies instead of gathering proof this is true, and you are assuming that this means we can't do anything as if there were a mechanism or a law that prevents "twin souls in a human body" to do something anyway.

All we can do is pray to God to help us get through all the lessons hopefully as quickly as possible.

If you assume the only thing you can do is to pray then of course if someone tells you that you can do else you may say "that's impossible, we can only pray". But that was just your assumption it doesn't mean at all that things work that way.

Then why is there so much chatter about manifestation ... what about all the 'everything happens in Divine timing'

It's two theories, and two that appear in opposition to most folks. On one side you have the "attractors" who believe in free will and that you have to paint your own rainbow, and on the other side the superdeterminists who believe everything is scripted and those who believe that higher beings manage your future.

So it's like you are asking: can I do something or not? And different folks will provide you with different answers.

Also some people have head-canons that contemplate variable measures of both views. For example for some people divine timing is not "God's intercession", it's more similar to "5D selves taking care of something", thus possibly opening a field of learning one lifetime might not be enough to get proficient about.