overwhelmed...where do I start

My fiancee lives in USA and Im in canada, we are looking into k 1 visas. I do not know what i need to do first before i get that one in. Can my son and I live down there with him while they are pending? If not, Will it be harder to travel and visit as customs will probably think I wont return?

First your fiance will have to send in the I-129F petition to USCIS.

No, you and your son cannot live in the US while it is pending. You can visit, but yes, you'll be scrutinized more at the border if you have a petition pending.

go have a look see at http://www.visajourney.com for marriage based immigration information.