Your template text should be replaced with the shortened (internal link) URL of the target page, Veronica.
In the link [[Special:Whatlinkshere/{{FULLPAGENAMEE}}|'''Profiles using Indigenous_Australians sticker''']], replace {{FULLPAGENAMEE}} with Space:Australia_Project_Maintenance.
Your link to your free-space should then be [[Special:Whatlinkshere/Space:Australia_Project_Maintenance|'''Profiles using Indigenous_Australians sticker''']].
The resultant page will not have any linked profiles unless you have linked your free-space to other pages. You can link to your free-space by adding [[Space:Australia_Project_Maintenance]] to relevant profiles.
Post back if you have problems with this process!
edit: The 2 links at the bottom of your free-space are basically linking to the same page, so you can just delete the second link.
If you are wanting to link to https://www.wikitree.com/index.php?title=Template:Indigenous_Australians_Sticker&redirect=no, then replace the template text in [[Special:Whatlinkshere/{{FULLPAGENAMEE}}|'''Profiles using Indigenous_Australians sticker''']] with Template:Indigenous_Australians_Sticker. You may also want to change the displayed text to differentiate between the 2 links.
Again, post back if you need more help!