CONFIG_16KB_2LEVEL is not available for thedefaultarchitecture x86.
Result is shown for architecture loongarch

16KB with 2 levels

configname: CONFIG_16KB_2LEVEL

Page Table Layout
└─>16KB with 2 levels
In linux kernel since version 4.14.326 (release Date: 2023-09-23)  
This option selects 16KB page size with 2 level page tables, which
support a maximum of 36 bits of application virtual memory.