After deploying wordpress6.0.1 I can’t get it to work

I rearranged my wordpress after my wordpress failure.
But it doesn’t work. A few things are known so far:
1. I can’t upload the media file, it says the file is too large.
2. The article cannot be published after editing, and the update fails. This response is not a valid JSON response.
3. The plugin cannot be enabled. After clicking Enable, it will jump to the update page, and then prompt that the plugin is disabled.
4. The theme cannot be downloaded, and an unexpected error has occurred. There may be some problem with www.remarpro.com or the configuration of this server. If you continue to experience difficulties, please try the support forum.

The site health check prompts the following information:
1. PHP sessions created by session_start() function calls may interfere with REST API and loopback requests. Active PHP sessions should be closed by session_write_close() before making any HTTP requests.
2. The REST API failed to properly handle the context request parameter.