Do you want to edit the color of internal links (links to other notes), external links, or both?
Depending on the theme you are using, there may be options in Style Settings, otherwise CSS. This should do it →
body {
--link-color: var(--color-orange);
--link-external-color: var(--color-yellow);
}
I set the color as var to show it, but you can change it to a hex.
