This is an example of usernames with an icons: utilmind — this is male user, and this is female user: Ludmila

And here is an expert tgerasimenko and celebrity account: Poмaн_Дaвыдoв.

However, the text with usernames can be larger (utilmind) or smaller (utilmind).

Unfortunately, static raster icons can’t be resized (utilmind), but SVG-based glyphs should allow resize.

Besides the username icons this site requires vector based siluettes. See cинтия or Vovapetrov user accounts to see legacy raster silhouettes.

BTW, I don’t mind if this raster silhouette will be traced and transformed to vector, but besides an User icon the updated website will it also require an Expert (professional specialist)  Celebrity (pop star or famous figure) and Moderator silhouettes, just like described in task at Upwork. Their look is on your decision.

This website will require more icons, but let’s start from small things from user account icons...

UPDATE

Here is some user icons from the FontAwesome collection:

 User

 Graduate

 Nurse

 Secret Agent

 Director (?)