You can create link on Notion by simply selecting the text you want to create the link on and clicking "link"
Here is an example link.
You can also create link to pages writing @ and then typing the title of the page you want to link
Here is an example: Typography
You can also use the “page link” blocks, these will take the full page width:
You can also mention people the same way as pages: @Tommy
Currently mentions in Notaku link to nothing, in the future you will be able to link to the use twitter or custom links
If you want something more visible, you can also create a bookmark block