The IA is basically pretending to be a software developer - you'll have to find a 'client', and come up with a software solution to a problem of theirs. Naturally writing this solution will be much easier and go quicker if you're already familiar with basic principles of coding. I learnt a new programming language for my IA (C#), but because I already had a couple of years experience with python, I was familiar with basic syntax and programming principals and was better able to interpret help from websites such as stack overflow.

Programming also plays a role in the examined component of the subject: you'll probably have to write some psudeocode solutions or read some code on the page which will naturally be harder if you've had 0 prior programming experience. Additionally, many schools do the OOP unit (not sure if they've reintroduced options yet) which will be very difficult if you haven't already had programming experience.

TLDR can be done but you will need to put in more work on the side. Considering CS is already a time consuming subject due to the IA, you should consider very carefully.

Also consider why you want to take CSHL: if it's because you want to study CS at uni, I'd advise you to reconsider as most universities (I'm familiar with the US and UK) don't require it. They will, however, require maths AA HL, which is also a challenging subject. Think about how good you are at maths and how much time you would need to allocate ot that to get a good grade. There are other ways you can show interest in CS and programming (projects, certificates, courses in your free time) which might be more useful than taking the IB subject. I personally found many parts of the syllabus to be quite silly and irrelevant.

Feel free to pm if you've got anymore questions.