I need to take the summation of the 4th column and it should start based on the first column and print at the 5th column at every entry of first column .
Your input file is not too consistent in its usage of spaces as field separators. It has one or two between fields, one up to six from BOL to $2 if $1 is missing, and zero or one at EOL. That's what " +" is for: it stands for "one or many" spaces. c.f. man regex for further reference.
awk ' ##Starting awk program from here.
FNR==NR{ ##Checking condition FNR==NR which will be TRUE when Input_file is being read first time.
if($0~/^[0-9]+/){ ##Checking condition if a line starts from digit then do following.
++count ##Increment variable count with 1, each time cursor comes here.
} ##Closing BLOCK for if condition here.
sum[count]+=$NF ##Creating an array named sum with index of count and keep on adding value of $NF to its own value.
next ##next will skip all further statements from here.
} ##Closing BLOCK for condition FNR==NR here.
/^[0-9]+/{ ##Checking condition if a line starts from digit then do following.
print $0,sum[++var] ##Printing current line and array sum with index of variable var with its increment of 1 each time cursor comes here.
next ##next will skip all further statements from here.
} ##Closing BLOCK for /^[0-9]+/ condition here.
1 ##Mentioning 1 for printing edited/non-edited line here.
' Input_file Input_file ##Mentioning Input_file 2 times here.