Add a tweak/feature to Wordpress

I have a Wordpress theme that I am working on - I want to add the following functionality/tweak (this can be through plugins or self-coded, as long as it works):

--> Only show a set number of posts on the home page - when non-registered users click on the image of the post they will get a pop-up asking them to either Login or Sign up using Facebook or email&password etc.

(Please see images attached to give you an idea)

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If this goes well, I have several more features that I will pass on to you.

Thanks

Please make sure you add the word 'understood' in capital letters on top to show that you have read the full requirements. And add the word 'complete' before understood to make sure :)

CSS JavaScript PHP WordPress

Project ID: #4581164

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