how to show ads in the middle of a post?

Select Before paragraph and put 0.5 for paragraph number.

thanks, anyway the centering the code blocks doesn’t work.

I use my codes like this, also selected “center” as Block Alignment and Style. but it doesn’t work. the ad isn’t centered.

<style>
.main_gads_res_css { width: 320px; height: 100px; }
@media(min-width: 500px) { .main_gads_res_css { width: 468px; height: 60px; } }
@media(min-width: 800px) { .main_gads_res_css { width: 728px; height: 90px; } }
</style>
<script data-cfasync="false" async src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script>
<!-- Link_Ads -->
<ins class="adsbygoogle main_gads_res_css"
     style="display:block"
     data-ad-client="ca-pub-xxxx"
     data-ad-slot="xxxx"
     data-ad-format="link"></ins>
<script data-cfasync="false" >
(adsbygoogle = window.adsbygoogle || []).push({});
</script>