Look, in general, I want to say that you have a chance to get a doctorate, I had Skype with many professors in this field, and they are completely open to students with a computer background, but there are a few issues that you should consider (my information about America).
These HCI courses themselves have many subcategories and you should look for professors who are related to your background to some extent, for example, I think you can find something in common in the field of ergonomics.
What I was asked a lot was what kind of research do you want to do that this change of field would help you, and this was a bit stupid for me, you don’t need to know very precisely, but it shouldn’t be general, in general, you want to know more and more precisely. What should you do and how will this field help you in your research? Your chances of being accepted will increase even if you have zero computer and programming background.
For example, after you have completed some of your research, look for courses offered in this field and say, for example, that a certain course will help my research.
You shouldn’t talk about design too much because they tell you to go and study
I want to talk about luck. There was a professor at Carnegie Mellon who had a student who had a bachelor’s degree in theater, which means that all majors and backgrounds have luck, you just have to convince them that you don’t want to change majors just because of interest and that you have a specific goal and research.
Overall, one of the backgrounds accepted by this field is design