Mahara does not have an admin interface to manage SEO tags. You would need to set them at the moment in a template directly.
Auto-publishing of journal entries is not a core functionality at this stage and I'm not aware of a plugin performing that functionality.
Mahara does have a couple of plugins for sharing on social media: See https://wiki.mahara.org/wiki/Plugins but they may not be up to date for the version of Mahara that you are using. You could implement a new block that would allow the sharing via a platform where you can turn on / off many social media sites.
Cheers
Kristina
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Thanks. God bless.
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