Multiple select drop down in android

You have to create a spinner in your own xml and create a custom adapter for that spinner.

These links may help you:

Multi Select Spinner with Search/Filter

How to develop Multi Select spinner

Multi Select Spinner

Multi Select Spinner with Search/Filter

Multi selection spinner in android without AlertDialog

You are talking about is Chips View, there are multiples third party lib which can help you

https://github.com/hootsuite/nachos

https://github.com/pchmn/MaterialChipsInput

You can get help from this.