when I create a clickable link I want to choose whether the link page should open in a new browser tab
Confluence cloud, create any page, and inside the page at some point insert a link, for example https://community.atlassian.com/
the link appears as it is. The only possible function is to present a replacement text to the url.
So if you save the Confluence page and then click on that link, your browser will go to the link.
So in the case of my example you will definitely exit Confluence cloud to land on the other website.
I wish you could choose instead of opening the links in the Confluence pages in a new browser tab, this way, you could keep the Confluence page without losing it.
I point out that this behavior already exists, for example, in the links that can be created in the left side of each Confluence space. The "space shortcuts" section. Here the logical behavior is that the clicked link opens in another tab, without making the user lose the Confluence space.