Purdue OWL Guide to Chicago Style 17th edition

Official Chicago Style Quick Guide

Sample paper:

• From OWL
• From Regent University

The standard manual for Turabian Style is
Turabian, Kate L.  A Manual for Writers of Research Papers, Theses, and Dissertations, Ninth Edition (2018).

Note that there are actually two Turabian styles:

• Author-Date (also described as Reference List) - Uses short form citations in text rather than footnotes or endnotes; bibliographic citations have unique format features.
• Notes (also described as Humanities or Bibliography) - Uses footnotes or endnotes; bibliographic citations have unique format features.

Official Turabian Style Quick Guide

What is the difference between Chicago and Turabian?

Essentially the two styles are the same, but there are some differences in style manuals:

The Chicago Manual of Style is designed for professionals in the field who are publishing and has a great deal of instruction on formatting and many other things. Turabian is a pared-down version designed for students writing research papers. 

Thus, if you see a citation in "Chicago Style" it is also in Turabian style.