You can administer a questionnaire to them, or rather choose to do interviews.

I am planning on doing that Sir. My only problem is on where do I base my questionnaire and the validity. Thank you so much for replying. Means a lot to me ☺️

It's hard to know how students' general epistemological beliefs applied to physics would be different from their general epistemological beliefs. However, the difficulty that some teachers face is subject-specific beliefs/attitudes – I should know, since I have been a music teacher and a statistics teacher in my time.

Here, you might consider drawing items from the research on attitudes to physics education. It would be interesting to see how specific attitudes towards physics related to general epistemological beliefs. you might search for literature around this paper :

Kaur D, Zhao Y. Development of Physics Attitude Scale (PAS): An instrument to measure students’ attitudes toward physics. The Asia-Pacific Education Researcher. 2017 Oct;26(5):291-304.

EDIT : I've just noticed your name – how utterly wonderful!

EDIT2 : epistemological, of course!

Wow! Thank you so much for replying to this question. I'm overwhelmed. Your thoughts of helping me really mean so much to me. I am not a savvy in research and I might be in need of lots of help but your message constantly bring me peace and definitely encourage me to do more with my research.

Thank you so much Sir Ronan for the compliment about my name and for your recommendation ☺️

Might I suggest a couple more edits, Ronán Michael Conroy? In two places, you wrote epidemiological beliefs where (I think) you intended epistemological beliefs. It's an easy slip to make these days when we're all thinking about COVID-19, vaccines, etc. ;-)

Alas, Sir Bruce Weaver , I have spent so many years writing "epidemiology" that my epistemologico-orthographic faculties have withered away!