By default, your Start.me page will open every link you click in a new tab inside your browser. If you don't want this, you can change the behavior.
Instructions
Click the User icon in the top right corner of your page.
Click Settings.
Toggle Open links in new window to off. It will turn grey.
Now, every time you click a bookmark, it will open in the same tab.
Note
When you click a Start.me page in the header, you will go to that page in the same tab. This behavior is not controlled by the Open links in new window setting. If you want to open a Start.me page in a new tab, press Crtl and click it.
Related article
If you have an issue with opening all links in a widget at once, read this support article.