He is widely regarded ______ one of the leading figures in quantum computing.

• Complete sentence: He is widely regarded as one of the leading figures in quantum computing.
- Bangla meaning: কোয়ান্টাম কম্পিউটিংয়ের ক্ষেত্রে তাকে একজন নেতৃস্থানীয় ব্যক্তিত্ব হিসেবে বহুলাংশে বিবেচনা করা হয়।

• Regard somebody/something as something
- English Meaning: to think about someone or something in a particular way.
- Bangla Meaning: গণ্য/বিবেচনা করা।

More examples:
- He is generally/widely regarded as the father of international law.
- Edith was widely regarded as (=considered by many people to be) eccentric.

অন্যদিকে,
• Regarded with (suspicion) - মনে মনে দেখা: regard with suspicion, সন্দেহের চোখে দেখা।
- যেমনThe bird regarded me with suspicion as I walked up to its nest.

• With/in regard to something - (in connection with) সম্পর্কে; বিষয়ে।
- যেমন: I am writing to you with regard to your letter of 15 March.

• Regard for [noun] - শ্রদ্ধা; সম্মান; সমীহ; সম্ভ্রম।
- যেমন: Jan’s regard for his great talent.

Source:
1. Cambridge Dictionary.
2. Longman Dictionary.