Hi Raj, welcome!
According to the help file:
Additional Features > Renaming From A Text File
Starting with version 2.2.6.0 it is possible to rename files according to a text-file.
This text file should contain a list of "old name" and "new name" pairs, separated by a pipe symbol ( | ).
To use this facility, create a text file in for the correct format, for example:
Track001.mp3|Headlong.mp3
Track002.mp3|Rushes.mp3
TRACK003.mp3|AnywhereIs.mp3
As you see, there is one entry per line.
Next, click the Import option on the File menu and load your file.
If the file is valid then you will see the "new name" column reflecting the contents of the text file.
When comparing the current filename with the text file the application ignores the case of the filename,
e.g. it will happily match Track001.mp3 and TRACK001.mp3. This makes it easy to rename the files.
...create an text file like:
ABCD_123.jpg|ASIN1.jpg
ABCD_123.tif|ASIN1.tif
ABCD_123.step|ASIN1.step
ABCD_123.pdf|ASIN1.pdf
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But for your case "I want to rename a group of files having same names but their extensions are different"
you just can do the same with the replace rule:
Repl.(3)
Repl: ABCD_123
With: ASIN1
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