Wrap them in a span and then color the span. Use a class name like checkmark and x.

See code snippet below:

.x{
  color:red;
}

.checkmark{
  color:green;
}

<ul>
  <li><b>HD</b> Available <span class="x">&#10006</span></li>
  <li><b>Commercial</b> Free <span class="x">&#10006</span></li>
  <li><b>Unlimited</b> Movies/TV Shows <span class="checkmark">&#10004</span></li>
  <li><b>Cancel</b> Anytime <span class="checkmark">&#10004</span></li>
</ul>

First off, you should realize that you don't actually need to use HTML entities – as long as your HTML document's encoding is declared properly as UTF-8, you can simply copy/paste these symbols into your file/server-side script/JavaScript/whatever.

Having said that, here's the exhaustive list of all relevant UTF-8 characters / HTML entities related to this topic:

• ☐ (hex: ☐ / dec: ☐): ballot box (empty, that's how it's supposed to be)
• (hex: ☑ / dec: ☑): ballot box with check
• ☒ (hex: ☒ / dec: ☒): ballot box with x
• ✓ (hex: ✓ / dec: ✓): check mark, equivalent to ✓ and ✓ in most browsers
• (hex: ✔ / dec: ✔): heavy check mark
• ✗ (hex: ✗ / dec: ✗): ballot x
• ✘ (hex: ✘ / dec: ✘): heavy ballot x
• 🗸 ( hex: 🗸 / dec 🗸): light check mark (poorly supported as of 2017)
• ( hex: ✅ / dec: ✅): white heavy check mark (mixed support as of 2017)
• 🗴 ( hex: 🗴 / dec: 🗴): ballot script X (poorly supported as of 2017)
• 🗶 ( hex: 🗶 / dec: 🗶): ballot bold script X (poorly supported as of 2017)
• ⮽ ( hex: ⮽ / dec: ⮽): ballot box with light X (poorly supported as of 2017)
• 🗵 ( hex: 🗵 / dec: 🗵): ballot box with script X (poorly supported as of 2017)
• 🗹 ( hex: 🗹 / dec: 🗹): ballot box with bold check (poorly supported as of 2017)
• 🗷 ( hex: 🗷 / dec: 🗷): ballot box with bold script X (poorly supported as of 2017)

Checking out web fonts for tick symbols? Here's a ready to use sample for the more common ones: A☐BC☒D✓EF✗G✘H -- just copy/paste this into your webfont provider's sample text box and see which fonts support what tick symbols.