1 my question is after i have crated a home on my desktop how do i then transfer to my laptop to work on the go,

Just copy the SH3D file to the other computer and install Sweet Home 3D on it.

2 is there a way to also save the file from the desktop to the online version so i can vue it from anywhere?thanks in advance!

No, but you can view the file on any computer where Sweet Home 3D is installed.