Is there a liquid multi-vitamin with fluoride for infants that tastes ok? The one we bought at the pharmacy smells strange and tastes bad too.

Depends. There are different formulas however, you may not like the smell or taste but your infant may not mind it. I would not give any Fluoride to an infant under 6 months.
No needed. Baby should be ok with mother's milk.. The vitamins craze is overblown... You really have no idea if these are from china and what they really contain.
Ask your pharmacist. Talk to your pharmaist about other brands. I have found that using generic formulas often have this result and ask patients not to get generic Fluoride supplements because of taste.