Notes on Migrating an iPhoto Library from iPhoto to Photos for Mac
How Photos handles content and metadata from iPhoto and Aperture - Apple Support
And I suggest that you get up to date with OS X 10.11 and Photos 1.1 - there are many fixes and improvements
as to editing - Photos is much better - you may have to add additional adjustments - in the edit window click on adjustments and then on Add and add the ones you want - there are more than iPhoto and they are more capable
and as to this
Plus, when I thought I was setting up a new album, I find that instead I've got a "file" instead, etc., etc.
I have no idea - you create a new album under the file menu ==> new album - the only way to create a "new file" with Photos is to export photos from it (file menu ==> export) so you need to give us details and contest
see Writing an effective Apple Support Communities question
We can not see you and can not help with abstract issues - you need to ask specific questions and provide details
for example adjust and enhance are default edit entries that are there all the time so somehow you are looking in the wrong place
TO edit a photos you double click on it to enlarge it and then click on edit
you also should always read the help topics and take the help overview for new programs
From Photos help on editing
You can use the Photos editing tools to easily make simple changes to your photos, such as rotating them or cropping them to get the best framing.

When you change a photo, Photos keeps the original so you can always undo your changes and revert to the original look.
Changes you make to a photo appear everywhere the photo appears in your library—every album, project, and so on. If you want to give a photo a unique look that appears in one version of the photo, first duplicate the photo and work on the copy.
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