Gujarat Mail - as good as Undhiyu

Usually, "macros" are used to automate repetitive tasks. If you are not into software, the easiest way is to "record" a macro. Like this:
1. start a macro recording.
2. start manually typing, making changes, etc. till your job is done.
3. stop the recording.
....
more...

Thereafter, when you "play the macro", it will automatically duplicate whatever key strokes you recorded - this way you do not have to tediously do the same typing again. In other words, all your manual typing that you recorded earlier, is automatically played back.
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If you want anything more complicated, then you would need to read the manual, search on the internet, etc.
All the best.