There are some strict rules about import data: https://wiki.openstreetmap.org/wiki/Import/Guidelines
Some people have imported data, e.g. in The Netherlands and in several cities in the US, but there is no fixed workflow.
A lot depends on the license, the quality of the data, the format and the available “tags”.
Please read the guidelines, and then continue on the import mailing list
Also I advice to learn more about mapping in OSM without imports before you try to do an import. Learn which data we expect, the quality, the tags that have to be used, etc.