Hi @raduansarif
Thanks a lot for your patience and hoping you are well, I would like to attach the SDK for MKL27Z128LH4 device that you can download from this link (once you are logged in): https://mcuxpresso.nxp.com/en/builder?hw=FRDM-KL27Z
Regarding the suggestions about MKL27Z128LH4 SDK, which specific suggestions are you looking for?
I just want to remember you that you can install the attached SDK into your MCUXpresso environment by dragging & dropping the .zip folder into the box as it is shown here:

At last but not least, J-link GDB server can be connected automatically once MCUXpresso is downloaded and installed in your computer, it will ask for you to install Segger J-Link driver and P&E driver if you want, so if you accept them, once you connect the USB from your development board, it will be detected automatically.
I hope all this information is helpful, if not, please let me know if you have more questions.
Best Regards.
Pablo Avalos.