Do we use does with who?

Excuse me, but I'm a bit confused about the grammar rule regarding the usage of "does" with "who." Could you please clarify for me? I've heard that sometimes "does" is used with "who" in questions, but I'm not entirely sure when and how it's appropriate to do so. Could you provide an example or two to help me understand this better? I'm particularly interested in how this rule applies in the context of formal writing or professional settings, such as in finance or cryptocurrency reports. Thank you in advance for your assistance.