Ficus Microcarpa Ginseng for the last 2 years. It hasn't died on me, so i'm going strong but it has a semi/dead part on it i want to maby treat into deadwood
This is not done on Ficus Ginseng (and if it is a garden center Ficus Ginseng, the one with the monstrous roots, it 's not really a bonsai either).
How do you water a tree that has deadwood on it
Exactly the same way as one that doesn't have deadwood on it.
if i water a dead part of a tree that part will rot instead of turn beautiful and white
It will not turn beautiful and white by itself. For this, on evergreens, we use jin seal. Again, on Ficus, this isn't done.