If you are truly a beginner and a serious student who really enjoys music, I recommend the three-book series of Alfred's Basic Adult Piano Course: All-In-One Piano Course Lesson Theory Solo starting with Level 1. I purchased Level 3 on Amazon.com. who has both new and used books available. Mine is spiral bound. I believe that there is a piano instructor on youtube who teaches levels 1&2, so before you buy go to youtube search for this book level 1 and listen to the videos. They are so helpful, taking a slow tempo approach and give some technique tips, according to your level of pianism that are very well done! When your book arrives you will be excited to see a complete Table of contents, broken down by sections, fun songs just for fun, comprehensive theory workbook pages, Lesson music scores, Scale and Chord Sheets, An Ambitious Section, Dictionary of Musical Terms and Certificate of Award.
The songs are varied in genre: Some Folk, Jazz, Rag, Pop, Spiritual, Classical, National, Holiday, Opera and others by over 20 composers. You will discover the joy of music in a stepwise fashion, learn to understand the rules of music theory and music definitions step by step, have solos to perform and enjoy the accomplishment of completing the lessons in Level 1 to receive your Certificate included, so you then will progress to level 2 then 3. I wish they included Level 4 Advanced- well maybe if we email them they will see the need to write levels 4&5- I sure hope so.
Also there is an interesting piano instructor on youtube withe a great sense of humor-PianoTV that I believe you will really enjoy after you complete level 1 or mat be evendors before. She provides interesting and entertaining videos on practically all aspects of learning music History, Appreciation, Theory (her videos show the specifics in everything from beginner tips, tutorials on how and what to practice to reading intervals and specific chord and music patterns and she provides free scores on her website. She did a beautiful "Oh Holy Night" tutorial for Christmas for Level 3 students.
Hope this sounds good to you-Best!