A person or thing having the same name as another person or thing -

A person or thing having the same name as another person or thing -  Namesake.

• Namesake 
English Meaning: A person or thing having the same name as another person or thing.
Bangla Meaning: একই নামে অভিহিত ব্যক্তি বা বস্তু; একনামা।

অন্যদিকে,
• Forename 
English Meaning: the name that is chosen for you at birth and goes before your family name.
Bangla meaning: পারিবারিক নামের পূর্ববর্তী নাম; আদ্যনাম

• Pseudonym
English meaning: a name someone uses instead of their real name, especially on a written work
Bangla Meaning: ছদ্মনাম 

• Nickname
English Meaning: an informal name for someone or something by friends or family besides original name.
Bangla Meaning: প্রকৃত নামের অতিরিক্ত। পরিবর্তে দেওয়া নাম; উপনাম।

Source: Bangla Academy Dictionary and Cambridge Dictionary.