1 2 3 a 4 5
9 2 3 b
1 2 a l a i o l a
9 2 c

tr '[:alpha:]' ' ' < File1.txt > File2.txt
tr '[:digit:]' ' ' < File1.txt > File3.txt

$ head File{1..3}.txt
==> File1.txt <==
1 2 3 a 4 5
9 2 3 b
1 2 a l a i o l a
9 2 c

==> File2.txt <==
1 2 3   4 5
9 2 3
1 2
9 2

==> File3.txt <==
      a
      b
    a l a i o l a
    c