1. Can the fermentation process be over in one weeks time make happen the bubbling is about to stop. If so how long do I shelve it back drinking it?
2. By adding more yeast and sugar after the fermentation process is complete, would the alcohol content be more?
Answers:
Chances are, you're not done fermenting but. Rack the wine into another fermentation vessel and let it sit for at most minuscule another month. The bubbling will slow down, but that doesn't mean it's stopped.
Don't spring the gun. A good fermentation will pocket 3-6 months before it's bottled.
And if you bottle it while it's still fermenting, they'll simply pop the corks and you'll lose your product.
If you want to increase the alcohol content, add a short time more sugar while it's still fermenting. It will jump-start the yeast and create a secondary fermentation. No requirement to add more yeast. But build sure anything you add after the initial is sterile (ie: dissolve your sugar surrounded by boiling water, after cover and let it cool earlier adding it.)
Go to the store where on earth you bought your initial ingredients/kit and get a book on winemaking. Either automatic, or with chemicals (which is much easier if you don't really get the biochemical reactions that are going on). It's dry reading (pardon the pun), but it's worth have the knowledge if you're interested contained by the hobby.
After all, it would be lousy to accidently breed ethanol and blind yourself, when the potential is there for the coolest hobby contained by the world. :)