Should learning English start with phonetic symbols or grammar? Please note that I have never learned English. What order should I follow step by step?

If you have never studied English, I suggest you start with letters. While learning 26 English letters, learn phonetic symbols and spelling rules. Once you learn the phonetic symbols, you can look up the dictionary to learn new words. With correct pronunciation and certain spelling rules, remember that the spelling of English words is not a problem. Learning word formation again will help to enlarge your vocabulary. Then learn grammar.