Hi Lan,
I highly suggest you use the MCUXpresso IDE, because you use the LPC before, the MCUXpresso IDE can totally compatible with the LPCXpresso IDE which you must familiar with it.
About how to get start with the Kinetis, you can refer to the KSDK, I don't know which kinetis chip you want to use now, but normally, each kinetis chip will have the according official board, this board already have the on board debugger (JLINK, opensda ,cmsis dap), just like the LPCxpresso board which contains the on board debugger LPC-LINK2.
If you are not use the official kinetis board, you also can use the LPCLINK2 to debug the kinetis chip, LPC-LINK2 already can support the kinetis chip, I have test it before, you can use the JLINK firmware.
About the peripheral module learning, please download the kinetis SDK code from this link:
Welcome | MCUXpresso SDK Builder
Wish it helps you!
If you still have question about it, please let me know.
Have a great day,
Kerry
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