Which client are you using?
can I post my cartoons here? ( like those at my bloggo https://csb.LOL )
and if yes, then where are images stored?
Discussion
I'm using https://coracle.social
If you want to upload images or video via client, these media files are stored on third party servers like nostr.build.
Some clients support upload from client. Not sure about coracle.
If you have a link to the jpg/png you could also post directly in a note and clients should render this an image.