Synch between iPhone and ipad

Is there a way to synch a project between the two devices without using the Dropbox feature ? I can’t seem to figure it out

Also for any IOS/iPad users out there; are there non fiction book format folder templates that are helpful in staying organized?

Thanks in advance for everyone’s help.
Finally getting back to a project I started 10 years ago- hoping to finish it this go around

I suggest you have a look in the Knowledge Base:

Plenty of information there.