You can upload a GEDCOM for comparison via GEDCOMpare. However, no profiles will be created at the time of upload.
As you compare profiles from your GEDCOM to WikiTree profiles, you will be able to edit those profiles that match.
For non-matching profiles, you can create new profiles using the GEDCOMpare process only after you see the Add button.
my personal advice:
- You should review the links above, as well as G2G posts that are tagged gedcom and gedcompare to learn the various pros and cons of the process.
- You should create and edit a few profiles manually first to familiarize yourself with the editing functionality.
- If you decide to use GEDCOMpare, start with a very small GEDCOM - no more that a dozen profiles - so you can process them without being bogged down by a seemingly endless number of potential matches to process.