First off - your tattoo artist should have explained all of this to you, especially if this is your first tattoo. If you decide to ever get another, go someplace that will spend time on you and explain everything - after all, tattoos are permanent and you deserve to be happy with it.
That said, let's see if I can help you.
1. It's different depending on the product. Most recommend using them for 2-3 weeks, but if you want to ensure bright colors and a smoother tattoo (smoother meaning not as raised up as many tattoos get, which is perfectly normal and has to do with the way you scar, not the tattoo) I would go ahead and use till all the scabbing is healed.
2. It is healed when all the scabs have fallen off ON THEIR OWN (never pick at a tattoo, if you pick off a scab and it starts to bleed, there is a chance that the skin with the ink in that area will be pulled off with the scab and you will have a blank spot in your tattoo) and the skin is no longer tender. If it is on your ankle, avoid shaving the area until the scabs are gone.
3. I'm not completely sure what he meant by "silver skin". What he might be referring to is the time when the skin is starting to scar and can be kind of dry and get a strange appearance over the top that can have a sort of sheen, like it metallic. But I'm not sure. You could probably google it.
4. That depends on your skin. That might just be the hair growing in under the scabs and should go away when the scabs go away. It might take until the tattoo is fully healed.
5. I start washing my tattoos with gentle, unscented, usually antibacterial hand soap the next day, three times a day, followed by tattoo-cream or neosporin. But if your artist recommended differently, then I would follow his directions, I'm sure he has a reason for recommending this. I would call him and ask when he recommends starting to wash it. If you don't want to, then wait until it scabs over.
I hope this helps! Some other advice: always always always wear sunscreen on your tat, the sun is ink's enemy. It can cause fading and discoloration over time. Also, most tattoo places give free touch-ups after a month or so, when the scabs are off and you can see if some of the color is uneven or there are empty spots (which is not uncommon), all you should have to pay for is the ink (relatively inexpensive) and a tip. If your artist did not offer this, I would call and ask because if they're a good studio, they should. Think of your tat like a scar, because that's what it essentially is. It has all the side effects of a scar - possible stretching, and sensitivity, etc. Enjoy your first tattoo and congratulations.