How to check and improve download speed

Hi All,
I have to Dev on Python to control chip EC200UEUAA that build on custom board and connect by serial port on OrangePI board.
I m very weak about python and never dev on uart, serial port and at command, please guide me about this below

Problem 1
I try to make script for download. by using QFTPOPEN, QFTPSIZE & QFTPGET (with comport), but I found my script has very slow download speed.
It around 3 minute for 1.8mb, eventhought I reduce serial port [timeout] to 0.1 then I make a loop for waiting end of response for each AT command
Question 1
1.1 Did It have AT Command for checking Internet speed ?
1.2 Did It have another way to download or speed up ?

Problem 2
I try to change baudrate from 115200 for checking about response and speed (AT+IPR=115200;&W) and then I can’t connect to chip anymore
Question 2
how I can reset It ? (I still not have any converter / adapter to connect with my PC, I have to tranfer my script into OrangePI to test)

Problem 3
My Vender make wire connect to usb port and tell my that I can simulate it as the normally connection as LAN or WIFI
I found new device as enx024bb3b9ebe5 from iwconfig and ifconfig, But still not have as ideas What I have to do next
Question 3
How I can setup for usb connection and make it as normally connection ?

Hi @thana6666
The download rate is not only related to the device Settings, but also greatly related to the wireless environment. Please help to check the AT+QENG=“SERVINGCELL” command and see the return result to confirm whether the wireless environment is good.