Medieval history link below. if link does not open then you cab search medvieval history on wikipedia.
https://en.wikipedia.org/wiki/Middle_Ages#:~:text=In%20the%20history%20of%20Europe,and%20the%20Age%20of%20Discovery.&text=The%20medieval%20period%20is%20itself,High%2C%20and%20Late%20Middle%20Ages.

Gregorian Chant link below.
https://en.wikipedia.org/wiki/Gregorian_chant

Gregorian Chant- Hildegard von Bingen: Alleluia

Notre Dame Organum
https://en.wikipedia.org/wiki/Organum

Rhythmic Modes
https://en.wikipedia.org/wiki/Rhythmic_mode

Notre Dame Organum

http://www.northwoodorchestra.com/resources/forney-the-enjoyment-of-music-11th-shorter-version-c2011.pdf
hello,
please read carefully. all links above are wikipedia links and few videos. please read and watch vedios and also textbook link is above. please also read from the text book.
Read Prelude 2 and chapters titledVoice and Worship: Tradition and Individuality in Medieval Chant,andLayering Lines: Polyphony at Notre Damein your textbook. I’ve also provided your outline, extra information and listening examples in D2L under Content: Medieval Period. 

after you done reading and watching everything please write 5 pages summary.