How to customize how field is displayed in view
If you just want to rewrite the file field in Views to something like

&lt;img src="https://url.com/sites/default/files/maps.svg"&gt;


All you have to do is


add that File Field in Fields section
Inside the File Field configure, select "URL to file" on Formatter
Inside the File Field configure rewrite results section, check the "Rewrite the output of this field" and rewrite something like "&lt;img src="[field_file] "&gt;" on Text area. Then click Apply.