Need help with creating a DAL and BAL as a dll

 I am a front end developer trying to learn back end. I need help with where to start in creating a project as a dll for data and business layers..
 I want to build an image gallery with 2 tables....Albums and Photos
tbl_Album
AlbumID, AlbumName, Description, IsPublic, CreatedBy, CreatedDate
 
tbl_Photos
PhotoID, AlbumID,Title,FullImage,ThumbNail, ImageType
 
Please help

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