How to call a so-called helper spelling to help reading a word?

Using words below as example:

team /tiːm/
head /ˈhed/
eat  /ēt/

The common syllable ea sound cannot always be pronounced consistently the same sound in English language. It differs per word. That's why there are e.g. tiːm , ˈhed or ēt coming along side in place to help us learn how to pronounce a word. In this question I call them helper spelling because I do not know how to call them.

How to call such a word, e.g. tiːm, ˈhed, ēt?

To help express my question: team is a word and what is tiːm?

How to call such a syllable, e.g. ə, i:, ē?

To help express my question: ea is a vowel sound and what is iː?

I want to find a list of such syllables e.g. ə, i:, ē so that I know how to pronounce a new word which I've never heard before e.g.

  Write          Read
  ---------------------------
  consistent     kənˈsistənt
  confluence    ˈkänˌflo͞oəns

I do understand that Google Translate can help you read words but it cannot give you knowledge related to above questions and I would to gain that knowledge.

This is called phonetic spelling or phonetic orthography. The International Phonetic Alphabet (IPA) provides a standard set of symbols, and is probably what you're looking for.