Code:
# nawk -F, '{x=0+substr($1,1,5)}(x>1200)&&(x<1230)' infile
0120123456,C,200,xcvfe
0120453576,A,201,fgsa
0120432343,A,402,dewa
0122344242,N,204,ghfs
# nawk -F, '{x=0+substr($1,1,5)}(x>1200)&&(x<1230)&&($2~/(A|N)/)' infile
0120453576,A,201,fgsa
0120432343,A,402,dewa
0122344242,N,204,ghfs
# nawk -F, '{x=0+substr($1,1,5)}(x>1200)&&(x<1230)&&($2~/(A|N)/)&&($3~/^2/)' infile
0120453576,A,201,fgsa
0122344242,N,204,ghfs
# nawk -F, '{x=0+substr($1,1,5)}(x>1200)&&(x<1230)&&($2~/(A|N)/)&&($3~/^2/)&&($4~/a/)' infile
0120453576,A,201,fgsa
#