Rather than correct, I'll just try and answer your question. I believe there is a place to post questions on italki and perhaps this would go better in there.
Anyhow!
Because 'My father' is not I, we or they, it is basically like 'one' we use has. As in 'He has had' or 'she has had'. This is the present perfect tense. It connects what is happening now with the recent past.
My father has had his car for two weeks now.
We use 'has had' because he still has the car and he has only had for a relatively short period of time.
If it was using the pronoun I then we could say, 'I have had my car for two weeks now.' Whenever we use he/she/one with the verb 'to have' it becomes has. The had bit is just because it is in the past.
http://www.bbc.co.uk/worldservice/learningenglish/grammar/learnit/learnitv343.shtml
Hope that makes sense! :)
1. When "have" means "possess", it doesn't have present continuous tense.
It's a status, not an act.
2. My father bought a car two weeks ago, and now he still owns it.
Present perfect tense is used when one act happened in the PAST, and it still lasts till NOW or has influence on the PRESENT.