Can users upload blog posts from the front end?

Sorry, but it's not possible at the moment, the WordPress blog feature works from the backend and they have an already really powerful editor with lots of blocks and features (and constantly getting updates).

If you don't want to grant access to the complete backend features to someone, remember that you also have the option to give users the role of "Editor", "Author", or "Contributor" https://wordpress.org/support/article/roles-and-capabilities/ which allows them to write blog posts from the backend but "locks" some of the other features.

Please remember that we haven't tested any front end submission plugins with the theme (they aren't supported), so they may require additional coding in order to fully integrate them.