There should be a job description attached to the advert with the person specification attached or at the back - all the questions in the interview should be around what they have put in the person specification. Probably it will be mainly around your knowledge/skills and experience, likely in a competency interview format. Google the 'STAR' format to structure your answers and go through thinking of examples of where you have demonstrated each area on the person specification, ideally from previous jobs but also any relevant study, placements, volunteer work and hobbies. For that kind of job I would expect them to ask about teamwork, how/when to escalate issues to clinical staff/seniors/management, communication, dealing with difficult patients/customers/parents as well as the areas you have already highlighted.
It is so so important you structure your answers (even if they don't specifically ask you to use the STAR format or give an example, you always should), and always evidence what you say, as NHS interview marking is quite rigid to ensure fairness, they will be marking you on a scale based on the evidence you give in answer to each question, it can be frustrating as an interviewer when you have someone who on paper seems great and clearly has good knowledge but just talks in a waffly rambling fashion about their ideas or theories of what they think about (e.g.) safeguarding, or what their team/organisation's approach to safeguarding is, rather than giving a nice concise example of when they have actually put it into practice. The latter can score higher even if it is a bit of a 'thin' example than the former as anyone can have great ideas but generally you want someone who actually can apply the knowledge in the appropriate context as well... so for example, if the question is 'Tell me about a time when you have contributed to good safeguarding practice', even if you have (luckily!) never had to actually report a safeguarding issue at work, you could for instance give an example of how you have encouraged others to be aware of their responsibilities/ensured they had the right training, or how you have shown you take your own responsibilities seriously by doing further reading or asking clarification questions or something similar?
Do remember also that a big part of interview success is coming across as the kind of person they want to work with, and this starts from the moment you step into the building - I know you will be nervous and its an artificial situation but things that can really help are smiling, open body language, good eye contact, being polite, responding in a natural -ish way to small talk designed to put you at your ease (I always have a little chat with my interviewees when I collect them from reception about their journey in, where have they come from, did they get parked up OK blah blah, I really don't care what they say but hopefully we build a little rapport!). All this just helps give the impression of you being a friendly, pleasant, confident person (even if you are a bag of nerves on the inside!)
Don't stress too much about your appearance, neat and smart (looking like you have made an effort) is important but you should feel comfortable too. Smart dress (or tailored trousers and smart top) with a cardigan or blazer over it, clean hair (tied back if very long or if you are likely to fiddle with it, otherwise down is OK), clean nails, not OTT, make-up, clean smart flats, brogues or court shoes is fine...