Usually to print a model it’s one of every part in the base directory of the zip file you download. Occasionally we will include variants or small printer parts, but they are usually in a separate folder.
Collect all the pieces printed by 3D printer. Then join them to form the figure. Sometimes a problem arises that we can not join them correctly. This is due to the faulty 3D printer output. Check them properly if it gives a faulty output or not. Learn about the working process and type of output from a facebook article. It will make easy to collect all printed pieces correctly.