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It’s hard to tell what we’re looking at from such a minimal screenshot, but is that your modeline? If so, you have definitely customized it (or used someone else’s customizations), so the answer is to examine those customizations and understand what they do.
I'd hazard a guess that the custom mode line is intending to display a particular icon, but that the font uses that codepoint for the "special character" shown in the screenshot rather than the icon that was intended. So changing fonts might also have the desired effect. (If changing fonts is an option -- if not, you'll have to change it in the mode line customisations.)
If you don't use that init.el file, do you see a problem? If not, you can bisect that file to zero in on what is causing it. IMO, it's always a bad idea to try somebody else's initialization wholesale. You are much better off starting with nothing and then adding in what you want one thing at a time.
(setq doom-modeline-icon nil)
if your config is for emacs or(setq doom-modeline-modal-icon nil)
if you use evil.