For the rest you may use the “export settings” function in the “personal settings” section on the webpage of your Lemmy instance (yet I don’t know what is actually exported).
Alternatively, you may use one of the tools mentioned in this post (the post is in German, the linked webpages are in English):
https://slrpnk.net/post/10923543
AfaIk, posts and comments cannot be exported.
For the rest you may use the “export settings” function in the “personal settings” section on the webpage of your Lemmy instance (yet I don’t know what is actually exported).
Alternatively, you may use one of the tools mentioned in this post (the post is in German, the linked webpages are in English): https://slrpnk.net/post/10923543