Migration Assistant Files

The files are put into the locations that they were in on the device they were migrated from (another Mac, a clone of your boot drive or a Time Machine backup of your boot drive), i.e. system files into the appropriate system folder, user files into the various folders that are owned by the user, i.e. Documents, Photos, Music, etc.

You log out of your current account and it will be right there. If you cannot see it then you must have botched Migration Assistant. The fastest and most reliable method to use MA is to connect the old Mac's Time Machine External Hard Disk to the new Mac and then launch MA. Any other method is iffy at best.

What files are you referring to? If it's photos io a Photos Library then the entire Photos library is migrated.

Migration Assistant created a new user account, all of the data you migrated is in that new users account.

Your welcome.