If I had my dad pay an attorney for my case, can he talk to him about the details of it? Can he pressure me to accept a plea?

Absolutely not. Nobody can force you to do anything in your criminal case. Moreover, your father paying for your legal fees does not entitle him to make decisions for you or know what you and your attorney discuss.

Classical lawyer ethics require the lawyer to obtain the asker's consent to have a third party pay the lawyer's fee, retain independent judgment during the case, and protect the asker's confidences.

There is very little here on which to base a response. The asker should see an attorney with his case file, his retainer agreement and all communications between the lawyer and the asker to get a response to this question.

Please do not message me here on Avvo. The original question does not accompany your message so I have no idea what you are talking about. Simply respond as a comment under the question and I'll see the comment and know which question your comment applies to. Always remember I am not establishing an attorney/client relationship with you here and I am not giving you legal advice for your case. I am only providing an education in the workings of the law using your fact pattern as an example and in no way am I helping you prepare your case for court. Further, I do not know your case. If you retained a lawyer, do not use Avvo to second guess your lawyer. Your lawyer knows your facts.