Pekin duck help?

I just got 2 female pekin ducks on st. Patrick's day from TSC and took a guess that they were about 5 days old? I have a half acre lake in my back yard with land and I'm wondering when they will start laying eggs? When can they go in the lake / outside? I'm getting a chicken coop for them so they are in a enclosure at night and wondering what I should use as bedding? Also they have a constant supply of food as of for now and I'm wondering if I should only feed them 3 times a day (breakfast lunch dinner) or have a constant supply also when they are adults. Lost of questions but I'm a little clueless, any advice will help related to the questions or not! Thanks!