For more info please check the components's official demos & documentation demos & documentation
<mat-chip-list> displays a list of values as individual, keyboard accessible, chips.
One fish Two fish Primary fish Accent fish

The MatChipInput directive can be used together with a chip-list to streamline the interaction between the two components. This directive adds chip-specific behaviors to the input element within <mat-form-field> for adding and removing chips. The <input> with MatChipInput can be placed inside or outside the chip-list element.

An example of chip input placed inside the chip-list element.

{{fruit.name}} cancel
{{chip.name}}