JSFiddle - React, Tailwind, and code Playground

HTML

<form>
    <input value="1" type="checkbox" id="admin" name="admin" />
    <label for="admin">admin</label>
    <input value="2" type="checkbox" id="security32" name="security" />
    <label for="security32">security32</label>
    <input value="4" type="checkbox" id="security64" name="security1" />
    <label for="security64">security64</label>
</form>
<button onclick="determineDownload();">Submit</button>
<div id="errfn"></div>

CSS

input, label, button, div {
    float: left;
}
input, button, div {
    clear: left;
}

JavaScript

function determineDownload() {
    if (!this.document.forms[0].admin.checked && !this.document.forms[0].security.checked && !this.document.forms[0].security1.checked) {
        document.getElementById('errfn').innerHTML = 'Make atleast one selection';

    } else if (this.document.forms[0].admin.checked && this.document.forms[0].security.checked && this.document.forms[0].security1.checked == 1) {
        alert('security32 and admin and security64');
    } else if (this.document.forms[0].security.checked && this.document.forms[0].security1.checked == 1) {
        alert('security64 and security32');
    } else if (this.document.forms[0].admin.checked && this.document.forms[0].security.checked == 1) {
        alert('security32 and admin');
    } else if (this.document.forms[0].admin.checked && this.document.forms[0].security1.checked == 1) {
        alert('security64 and admin');
    } else if (this.document.forms[0].admin.checked == 1) {
        alert('admin is checked');
    } else if (this.document.forms[0].security.checked == 1) {
        alert('security 32 is checked');
    } else if (this.document.forms[0].security1.checked == 1) {
        alert('security64 is checked');
    }
    return false;
}