I strongly suggest that you spend some time with the Wiki, as this is really a very basic question.
Well, the Wiki is not really easy to understand for a newby, all 161 pages of it. I went there, found the magnifying glass and did a search for "create new album" and got four results meaningless to me, a newby. The problem is the Wiki is written and maintained by Hero members who know all the sophisticated concepts, know and use all the obtuse jargon and methods, in what is a very sophisticated program.
A better answer, phred, would have been to say "Go to the Musicbee 101 Tutorial to learn the basic concepts" if there is such a thing (I haven't found it yet). Look at the words in your answer, phread, dismissive and demeaning, don't you think?
iTunes refugee. Six SONOS zones. Harmony Elite Remote/Hub. Alexa enabled house. Using MusicBee for curating music (managing library, creating playlists, etc.). Thank God I'm a Systems Engineer.