I'm in a situation where I need to copy a solid body that has no connection to the parent body? Is this possible?

I need to make a copy of body A, cut a part away from the parent ( body A), combine the parent with the copied part (body b) and keep the difference, or the negative space from the first part. the hole is fairly compex and there are quite a few of them, so creating solid bodies from surfaces that match the inner surfaces would be very time consuming.

I come from a 3d max background where the copy feature offers you three choices before creation of the copy:

Copy – creates a stand-alone copy of an object; changes to the copy or parent or either of their modifiers do not affect the original object.

Instance – creates a mirror of the original object; changes to the child and its modifiers affect the original object and all other children. And visa versa, changes to the parent affect all children.

Reference – creates an object based on the original; changes to the parent will affect all its children, but changes to a child will *not* affect the parent or any other children.

Using this I need to create a Copy of a solid body

Any help would be.... well, helpful.

Thanks