Covid Positive related. I avoid it?

My father has been tested Covid positive after the first dose of vaccination. He is 57 years old and is heart patient. His CT value is 26. He was ill from 20 days after the vaccination but test was done on 12th may 2021 so he seems to recover himself. Symptoms- Mild fever 99.5, mild cough and cold, no difficulty in breathing with oxygen level  99 but has weakness in body. Current medication- only PCM Query- I just wanted to ask whether we need to give any medicines to my father or not?. I have already purchased Azithromycin and Montair LC but i am afraid to give him these antibiotics as he is already heart patient so dose may be higher for him....or else it may react with vaccine. So please suggest me what to do. Whether to give him any of these medicines or not for infection? Is it safe or shall i avoid it?