All the parts can go together in a myriad of ways, although some are “better” than others. And if the parts are put together wrong, there is a chance that you can pull it all apart and try again. But forcing things where they don’t belong will just result in pain and frustration. Better to take it slow and figure out how things seem to work together best.
My daughter, 6.5, put this little plane together. It’s plastic, similar to a credit card, and came on a single sheet with no instructions. She was able to put it together based on the very small image on the card. After getting it almost done, she couldn’t figure out where the very last piece fit. So she came to me to figure it out. It took me several minutes, but I finally realized that the last piece was a base so that it could stand.
She realized that all the pieces were important and rather than forcing them, she looked for help. And now her teeny tiny plane is able to stand on its own.