My Ph.D struggle at the very begging. Need advice

Hello. I'm doing PhD in Law. I just started it like a month ago. Problem is I still cannot find a common language with my supervisor with regards to research topic. We have been changing topics like 5 times. And every time I come up with an idea that initially my supervisor supported, he finds problems with it and suggests something else. Then I research a little, come up with idea, then the same thing. We seem to speak the same language, but I kind of feel that he is not happy with my ideas and sometimes he even questions my knowledge about particular area and wants me to read again stuff that I've read through my Bachelor's and masters. I can't understand, if he was so unsure about my knowledge, why did he choose me in first place. I don't know how long will it take Untill we concretize the topic and finally I'll start research on my topic. This situation makes me question my decision of even doing Ph.D, because it is draining to see that you professor is disappointed and doesn't get what he thought he would get from you. Is it something that I face only, and how should I deal with it? How can I motivate myself?

Keep at it. It must be depressing but you are only 1 month in and this is the perfect time to discuss projects. Thinking of potential problems now saves so much time later . You don't want to get a year in to find the research is a dead end. It is not that he is unsure of your knowledge but he is trying to guide you towards a project that will work. I have seen people change projects 2 years in because the supervisor just agreed with the student. I would be more worried if it was 6 months.

Though have you decided a general area of law you want to do? That is a good first step to whittle down your options and you just keep making the area smaller and smaller until you have a research question.

You are way too early to be worrying about this.

Is your supervisor correct when these eventual objections about your ideas are raised?
Evaluate what is causing problems in your original ideas and use this to learn how to better evaulate further ideas yourself. Eventually the idea is that you'll learn to produce ideas which won't be easy to dismiss and you'll have your solid ground.

Thanks guys for the comments. So the area of law is clear. It is very progressive IT law and all the new stuff visa vis legal regulation. It just seems that I am either proposing a broad topic or a topic that isn't dissertable. He is very bright and I think he just wants to dig into my brain and make sure that I don't have any fundamental legal gaps. But that being said, I still feel like the topics that he is suggesting are like literally very narrow. Another question that pops up is whether these topics are even my products or his products that he doesn't have time to research, and delegated to me to do it.

Your PhD doesn't need to be a single question.
It can be a series of related problems which overall form a body of work in a specific area.

For example, I started out by taking on ideas from my supervisor and then expanding them as I did the work and saw other opportunities. By the end I was making up my own ideas and implementing them.

This method is much less risky than looking for a single massive question to work on and you get lots of smaller wins along the way. It could allow you to quickly implement some very narrow and specific ideas of your su-pervisor before gradually moving on to take over yourself.

You could perhaps adopt this method.

Don't worry! You are only a month into it. It took me and my supervisor at least a year to decide on a topic since I kept changing my research questions. So yes you are not the only one.