Merge 2 html file in first html file

Learning Hub
1

How to merged 2 html file in first html file.
I want merged html1 and html2 file in first html file.

2

@kailas.kokate Can you please share both the html file?

3

Due to company policy I cant share both file but I could explain.

SourceFile:
1: word1
2: word2
3: word3

DestinationFile:
1: word1
2: word2
3: word3

If SourceFile Changes
1:Word11

Then DestinationFile:
1:word1
2:Word11
3:word2
4:word3

DestinationFile Should:
1:Word11
2:word2
3:word3

But in current workflow not working
Please help