I would want the assistance of someone who will provide me with a link to download Cambridge Latin course book 3 or upload to upload if you have
As Rafael rightly pointed out, providing download links to copyrighted material is illegal, and thus beyond the scope of this site. However, the book you are asking for (Cambridge Latin Course) is, for the moment, freely accessible online (and online-only, i.e. no downloads) here. Notice the disclaimer though:
We have put our Cambridge Latin Course textbooks online on this website. Access to these 'WebBooks' will eventually be via paid subscription, but for now they are freely available for you to try.
And later on:
Students and teachers may start using the WebBooks now, either individually or with their classes. It is likely that we will introduce a paywall for access by 2018.
Clearly hasn't happened yet.