My website shows a hyphen on the browser tab, as well as in front of the website name when I search it in google. I don’t know where this hyphen is coming from. Any idea on how to fix it?
That hyphen is the separator between your site title and tagline, which the theme normally displays in the title tag but which you left empty in WordPress’ general settings.
Either fill in the title and tagline in the settings or use a SEO plugin to customize the title that your site should display to browsers on the homepage.