Check out example codes for "icon material design google fonctionnemnt". It will help you in understanding the concepts better.
Code Example 1
<i class="material-icons">account_balance_outlined</i>
<i class="material-icons material-icons-outlined">account_balance</i>
Code Example 2
<link href="https://fonts.googleapis.com/icon?family=Material+Icons" rel="stylesheet">
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