uploaded custom font keeps rendering as times new roman

use woff2 if you're not already. and if this is wordpress, some setups block font files in the media library upload, so the file you think is there never actually uploaded. check the url in the network tab actually returns a font, not a 404 or an html page. also a site on https loading the font over http will get blocked as mixed content.

Times New Roman means the browser gave up on your font and fell back to its default. Open dev tools, Network tab, filter by Font and reload. Either the font file is a 404 (wrong path in the @font-face url, remember it's relative to the CSS file, not the page) or it loads but gets blocked. Blocked is usually CORS: fonts served from a different domain or a CDN need an Access-Control-Allow-Origin header, otherwise the browser refuses them. The other classic is the name, the font-family in your CSS has to match the name in @font-face exactly. And add a proper fallback like sans-serif so a failure at least looks okay.