How to get rid of spams and trackbacks?

There are some plugins that may help:
https://www.ads-software.com/extend/plugins/antispam-bee/

https://www.ads-software.com/extend/plugins/simple-trackback-validation-with-topsy-blocker/

You could disable trackbacks:
https://codex.www.ads-software.com/Combating_Comment_Spam/FAQ#I_have_disabled_trackbacks.2C_but_trackbacks_continue_to_be_posted

You could also rename wp-trackback.php
https://codex.www.ads-software.com/Combating_Comment_Spam#Comment_Spam_Hacks

You could put the following in your .htaccess:

# Block all trackbacks
RewriteCond %{REQUEST_METHOD} =POST
RewriteCond %{THE_REQUEST} ([^.]+)/trackback/ [NC]
RewriteRule .* - [F]

I’ve been able to reduce my comment spam considerably:
1. disable trackbacks
2. moderate all comments
3. use SI CAPTCHA plug-in on comments
3. add a line to the php code stating:
All comments are moderated.
This line prevents the type of comment spam that is not automated. It is easy to add. Find the comment-template.php file in the wordpress/wp-includes folder; then add this code:
<B>All comments are moderated.</B>
before the phrase:
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