Hello liuqimin,
First of all, inside your config block the "Download code after build" option was unchecked, so probably the board was not even flashed with the generated and compiled code.
Secondly, after I flashed the board, the FreeMaster ("borrowed" from our ftm_pdb_adc_chaining_s32k14x.mdl examples) the ERRCH0 was 1, which means, according to the RM that a conversion is started when another conversion is in progress.

What I did, was to change the SC1 Register from B to A. Now it works. Probably it needs to start with the first SCI register and complete them in order starting from A...

For measuring the potentiometer on the board, I also connected the PTC14 (potentiometer) with PTB12(your pin selected in the ADC read block).

Tips: On the S32K144, please be sure that you power the board on the external J16, and the J107 is connected between pins 1 and 2. If nothing of this works, please try using another board.
I also attach the Simulink model and the FreeMaster project modified.
Hope this helps,
Marius