Which Hardware Emulator and Development IDE/Editor is best for Embedded Development

I am new to the embedded development area and doing self-study in this area (I am already from Computer Science background) but I have few doubts and need guidance on the development and testing tools used in this area.

Q1. What is the difference between :-
openOCD, pyOCD, Segger J-Link,

Jumper Virtual Lab,
https://www.thefreecountry.com/emulators/arm.shtml
QEMU CPU Emulator,
ARMware,
Microsoft Device Emulator 3.0,
Softgun - the Software ARM,
SkyEye

I am confused between an...

Which Hardware Emulator and Development IDE/Editor is best for Embedded Development