Hi, I am unable to build kernel. Can anyone please help ? I am following steps from here: https://kernelnewbies.org/OutreachyfirstpatchSetup sumitsum@sumit-personal:~/Documents/linux_kernel/git/kernels/staging$ make -j3 YACC scripts/kconfig/zconf.tab.c /bin/sh: 1: bison: not found scripts/Makefile.lib:210: recipe for target 'scripts/kconfig/zconf.tab.c' failed make[2]: *** [scripts/kconfig/zconf.tab.c] Error 127 make[2]: *** Waiting for unfinished jobs.... LEX scripts/kconfig/zconf.lex.c /bin/sh: 1: flex: not found scripts/Makefile.lib:195: recipe for target 'scripts/kconfig/zconf.lex.c' failed make[2]: *** [scripts/kconfig/zconf.lex.c] Error 127 Makefile:525: recipe for target 'syncconfig' failed make[1]: *** [syncconfig] Error 2 make: *** No rule to make target 'include/config/auto.conf', needed by 'include/config/kernel.release'. Stop. make: *** Waiting for unfinished jobs.... -- Thanks and Regards, Sumit