Split a column in to two columns bash Linux

With awk:

awk 'BEGIN { cnt=1 } /^$/ { cnt++;next } { if (cnt==1) { map1[cnt1++]=$0 } else { map2[cnt2++]=$0 } } END { for (i in map1) { print map1[i]" "map2[i]}}' file

Explanation:

awk 'BEGIN { 
             cnt=1                                            # Initialise a column counter to 1
           } 
      /^$/ { 
             cnt++;                                            # When there is a blank line, increment the cnt variable
             next                                              # Skip to the next line
           } 
           { 
             if (cnt==1) {    
               map1[cnt1++]=$0                                     # If cnt is equal to 1, set an array map1, with an index as an incrementing counter (cnt1) and the value as the actual data on the line ($0)
             } 
             else { 
               map2[cnt2++]=$0                                     # If cnt not equal to 1, follow the same logic as before but use array map2 instead
             } 
           } 
       END { 
             for (i in map1) { 
               print map1[i]" "map2[i]                          # Loop through map1, printing the entries as well as the corresponding index entries for map2
             };
           }' file

I am trying to do it with out a bash script if possible. Thanks in advance!

The pr utility can do that without the need for scripting, not saying that scripting is not needed but there exist a tool just for that purpose.

pr -t2 file.txt

To use a space to separate the columns.

pr -t2 -s' ' file.txt

See the man pages for pr for more info.