You do not upload the BAM file of the Big Y to Yfull yourself, but indicate where it can be downloaded. You get the link for this at FTDNA after you have bought the BAM. To do this, you first log into your account and go to the page with the results for the Big Y.
If you have done your Y-STR test at FamilyTreeDNA, the Y-haplogroup is predicted very conservatively. To get a better prediction you should definitely join the appropriate Y-haplogroup project. The administrators of these projects can group you more closely based on your STR markers.To join the projects, you first have to register at FTDNA with your …
You don’t upload the raw data BAM file of the NGS test to Yfull yourself, but indicate where it can be downloaded. You can get the link from the provider where you did your test. (FTDNA, YSEQ, FGC). Companies like Dante Labs don’t offer such a link for Yfull directly, so you have to make the required file accessible via a cloud.