Hello and welcome @Elizabeth_Solomeina!

Sync is a one-way process so you can not add, edit or delete records in the synced destination table. In order to add information (via a form) to a synced table you’d need to create a form to add a record to the Source table, then once completed, that new information would be sent back to the destination table via the Sync.

Let me know if I can help provide any more information, and if this helped answer your question please mark it as the solution .