I'm sorry, but I don't understand what you are referring to. If this is for API keys (not the same as software key) V3.20 supports up to API V1.0, while V4 supports API V1.0 and API V1.1.
API V1 one doesn't have a way to upload images associated with a given user but you can override the default API. Copy the default app/routes/route.api.php file to app/routes/overrides/route.api.php folder.
Forom :https://v3-docs.chevereto.com/api/#api-response