To find the fonts used:
Right-click on the generated text and choose "Inspect" to open DevTools. Look in the "Styles" tab for the font-family property. It will show the fonts applied to that element.
Open the "Network" tab, reload the page, and filter by "Fonts". This will show the font files (.woff, .ttf, etc.) used by the site.
Some fancy text generators like name-style.net use Unicode symbols instead of custom fonts, so you won't find additional fonts—just different Unicode characters