A: The person that gave me Molly said she was fixed but I don't see a scar. Is that normal?
My furbaby isn't fixed yet, but my cat did, it didn't leave scar 
B: Molly if I don't hold her and just sit on the floor she will rub her back against me or the furniture. Again is that a yorkie thing?
that's very sweet of her, my baby wouldn't do that, she LOVES running and jumping, but she will still comes to me, sit on my laps when she's done
C: How much and what do you guys feet your yorkies I am using Iams at the time.
I wouldn't choose Iams, it's famous but I've read it's not really the best, I'm currently giving Sugar Addiction salmon, Orijien and Innova are good too!
You may check this site Dog Food Reviews - RateItAll
D: What kind of
[COLOR=green ! important][COLOR=green ! important]vitamins[/COLOR][/COLOR] do you guys use?
I give her supplements as treats, Cod liver oil, conditioning tablets with B complex vitamins, and some other garlic or yeast tablets.
Lots of brands in the market, I'm still searching the best one 
E: Molly also does not drink much, at least I think she does not drink much. Again is that normal? But she does pee.
When Sugar was very young, about 2 to 4 months she didn't like to drink water, but recent months she started to drink a lot
That's all I can help, welcome to YT! 