Hi Diptesh Kumar,
To make Other Git option available under Pipelines, you have to turn off Disable creation of classic build pipelines option under Organization Settings.
I faced the same issue:
To make Other Git option available under Pipelines, navigate to Organization settings=>Pipelines=>Settings=>General
=> Turn off Disable creation of classic build pipelines option.
Now, the Other Git option is available under Pipelines=>Connect
Hope it helps!
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