Chinook Dictionary by Shaw https://archive.org/details/chinookjargonhow00shawuoft
This is an excellent piece developed by the Grande Ronde Tribes of Oregon on words and etymologies https://lingpapers.sites.olt.ubc.ca/files/2018/02/2010_Zenk_Johnson_Hamilton.pdf
Read or download Jay Powell’s Chinook Jargon textbook The Language of the Northwest Coast
This is a great introduction to Chinook Rudiments of the Kamloops Wawa writing system https://open.library.ubc.ca/collections/bcbooks/items/1.0308127
You can read Kamloops Wawa newspapers as well as an affiliated newspaper Sugarcane Tintin here: https://www.canadiana.ca/view/oocihm.8_04645
Duane Pasco was one of the first to develop learning materials for Chinook Wawa. You can find entertaining reading here: https://www.duanepasco.com/tw/sj01.htm
BC Chinook Wawa has been pleased to support one of the best Chinook Wawa scholars in the world David Robertson. You can see his excellent blog here: https://chinookjargon.com You can see his PhD dissertation here: http://dspace.library.uvic.ca:8080/handle/1828/3840
Of course Dave’s site is your best resource. Dave’s thesis is also very helpful.