JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://unpkg.com/vue/dist/vue.global.js"></script>
<script src="https://unpkg.com/@vueform/multiselect"></script>
<link rel="stylesheet" href="https://unpkg.com/@vueform/multiselect/themes/default.css">
<div id="app">
  <input type="button" value="add option and select it" @click="addOption" />
  <div>{{ debugOutput }}</div>
  <Multiselect
    mode="tags"
    v-model="values"
    :options="options"
    :allowAbsent="false"
  />
</div>

CSS

body {
  font-family: Avenir, Helvetica, Arial, sans-serif;
}

JavaScript

const app = Vue.createApp({
  setup() {
    const options = Vue.ref(["o1"])
    const values = Vue.ref(["o1"])

    function addOption() {
      const newOption = "o" + (options.value.length + 1)
      options.value = [...options.value, newOption]
      values.value = [...values.value, newOption]
    }

    const debugOutput = Vue.computed(() =>
      JSON.stringify({
        values: values.value,
        options: options.value,
      }),
    )

    // expose to template and other options API hooks
    return {
      options,
      values,
      addOption,
      debugOutput
    }
  },
})

app.component("Multiselect", VueformMultiselect)
app.mount("#app")