Migration of SharePoint 2013 site to 0365

Hi All,

We are all set to migrate our SharePoint 2013 sitecollection  to 0365 one by one in a  row.

First we need to know the steps to work on.? we are not in a position to buy any tools to migrate from 2013 -On premise to 0365 .

Please find my questions below

1: what are the prerequisites required to migrate from 2013 to 0365(apart from licensing).?

2:Steps how to migrate 2013site collection to 0365 site collection.?

3:How to migrate any customizations.?

4:How to migrate workflows.?

5:How to set up the local Active directory to 0365 domains.?

6:How to move the data.?

Please reply to my questions above.if possible please give me the micrsoft contact person who can help in all the aspects.

Thanks in Advance

Rajesh