When I join and I see myself in a tree, how do I claim that as me? How do I associate my account with that record id? And then am I the only one who can edit my stuff?
Since you are living, you should not be able to see yourself anywhere in Family Tree. If you can, then someone has entered you deceased and you need to change that.
The only exception is the record of yourself that you created to start working in Family Tree. Likewise, only you can see the profiles of living people that you create.
To summarize the other post, the editing permission rules are simple:
Basically, you don't have stuff here. Once you contribute it to FamilySearch, it is theirs, not yours, and they let all of us users share in the work of perfecting it.
To answer your question we need a tiny piece of additional information. Is the "you" marked living or deceased?
This discussion seems to relate to Who has permissions to edit people in my family tree?
Sure you should INDEED be able to see yourself in the family tree - -- but it is a record in the private space of the family tree - based on information the user themselves entered when they created the account. Only The Living person who created it can see it - and no one else.
I see my own record - every time I log on -- - connected to my parents who are deceased. (I created my own record) - but no one else sees it -- it is part of the "private space" area of the tree that I see.
You can see your own record in the pedigree view by clicking on the "HOME" icon
and then you will need to start adding to it - parents, grandparents etc,
this is the home icon -- that will take you back to your own personal record - which you can then build upon by adding parents/grandparents etc,