Loosely, yes. The first film explains how Tang Sanzang meets Monkey King and the Pig. The second film focuses on their rocky relationship. You can watch this as a standalone, but the emotional punch of the ending will be lost.
If your search for "download" was intended to find a digital copy, here is the current status: download journey to the west the demons strike back top
If you have a subscription to certain streaming services, you may be able to download the film as part of your plan: Loosely, yes