Okay, welcome! Good to see you are familiar with some birds, anyway!
Search this forum - there are so many good bits of information!
If you can get a copy of Storey's Guide to Raising Ducks, that will help immensely.
There is also a duck web site from a research center on Long Island (sorry I don't recall the url).
Some brief notes:
First week, 90 degrees F, dropping about 5 degrees a week until they can handle the temperature of their environment.
Food and water before them at all times until they are several weeks old. I waited till they were six weeks old to take food and water away at night, and then only six to eight hours.
No food without water - they are likely to choke.
Water and bedding will be your biggest management challenges if you are like most of us. Place something under the waterer or make a waterer that resists splashing.
Ducklings can drown, easily, for a number of reasons.
Ducklings need to be able to wash their entire heads, daily if possible, to reduce risk of eye, sinus and respiratory infection.
Storey's recommends 20% protein the first two weeks, 18% from three to six, and 16% afterward until laying or high stress situation.
Ducklings need three times the niacin chicks do - remember this if for any reason you want to just use chick starter.
Ducklings also are harmed by some medicines in feed. Unmedicated is safest, there are some on the forum who advise that some medications are fine, even desirable.
Mold is potentially fatal to ducklings.
Ducklings can get into very surprising difficulties - they will eat things, jump into things, pull things down, knock things over, when you least expect it.
Ducks are very susceptible to predators - domestic and wild.
Ventilation is important - cold breezes are not good, but there needs to be fresh air.
Their needs change sometimes every two or three days - they outgrow a waterer, they grow so rapidly it can make your head spin, they begin to appear bored and restless, they start sneezing or panting . . . . try to pay attention and deal with it early.
Salad greens are excellent additions to a balanced ration, check out the sticky on treats for guidelines.
I will send this on and hope it helps.