Can the appium server send multiple instructions to the mobile phone for execution at the same time

Excuse me, the process of manipulating the mobile phone to execute scripts through the appium server is to execute the next command after one command is completed. Can you transfer all the commands to the mobile phone and then execute them together?

No. There is no queue. It is a command/response algorithm. Please see, ‘How HTTP Works’ on this page:

HTTP is what’s called a stateless system. This means that, unlike other file transfer protocols such as FTP, the HTTP connection is dropped after the request completes. So, after your web browser sends the request and the server responds with the page, the connection closes.

This is possible with native automation frameworks, like xctest for iOS or Espresso for Android. Otherwise the Webdriver protocol Selenium and Appium are based on would make no sense.
Although, there is a possibility of “batched” commands execution on the server side. Check https://appiumpro.com/editions/85-batching-appium-commands-using-execute-driver-script-to-speed-up-tests for more details.