Two Names Confusion?

[m_and_m]

Some of my dad's documents such as passport, birth-certificate etc. have an extension "kumar" added after his name while the other documents do not include "kumar".

As you know it is very common to add extensions such "kumar", "lal", "bhai", "ben", etc. back in India.

Would this cause an issue? Do we need to make an affidavit for clarify my dad's name situation?

[immihelp]

Not back in entire India, just in Gujarat.

Write the name as per the passport in all visa documents.
While filling the forms, write other names in 'Other names used' column.

Let's assume, someone's name is Suresh Patel.

And different variations are
Sureshbhai Patel
Suresh Kumar Patel
Suresh Gangaram Patel
etc.

In such as situation, do what I just wrote above.

Also, get one affidavit prepared by him. https://www.immihelp.com/sample-one-...s-immigration/