Many things a are matters of beliefs and faith, opinions and religions. Beliefs, opinions, faith and religions cannot be really presented as proven facts.
So basically you cannot really ask people to prove you that any form of higher power (which we call "god" or"goddess" ) from any specific religion, that you can get your desire by lighting a candle and manipulating your energy, etc..
Asking someone to make you believe in any form of high power, god or goddess, and any other magickal concepts is not something that you need to do if you wish to believe in any form of magic's and the universe's unique powers' existence. Such actions are called "preaching" ( or just trying to make you believe in something by forcing) and to be preached is something extremely not recommended since sometimes it can be a brain-wash and might be done against your free will. You do not need anyone to prove you the existence of a higher form of power and any other magickal concepts. This is really not necessary and even not recommended, as I said.
If you wish to believe in any form of magic, higher power and being (call it god or goddess if you wish), just do it.
If you wish to be an atheist and not to believe in god, goddess (higher powers) or any form of magick - than do this.
So if you are confused about the existence of any magickal conceptand you want someone to "prove" it to you, here is my recommendation for you:
Take your time. Be neutral, do not say a total "no" or "yes, I do". Time is a cure for many particular cases, and i must say that it really suits yours.
Think for yourself "is there any higher form of power. Is there magick? " , "should I choose any religion to follow?" , "should I start believing or not?".
As I said, take you time and start thinking what you are going to do. If you decided something, you are always able to change your mind about it and act differently - because you are the one who decides what actions to take and what moves to make.
If you come to the conclusion that currently, following any religion or believing in any form magick and deity is not for you - just follow you heart and opinions. If you do decide that you choose to believe, and follow something, then do it. As I said, you can always change your mind.
But as I said- it is about you and your decisions. Do what you will. You do not need anyone to tell you "yes" or "no". You are the one who chooses if to follow unproven and unseen theory and belief system or not.
Also if you wish to test the existance of magick why won't you just try it? You can take some time to learn about magick and witchcraft, practice few forms of magick and then see what the results are. Though, remember that many magick practices are associated with energy manipulation which basically needs faith in yourself and what you do to be effective. Also yes we can share experiences with you and assure you that magick is real if you have faith in it and in what you do. We actually had a thread about magick and faith togeter, but I think that it is not to relevant for this thread. If you wish to view the thread that talk about how faith effects magick, feel free to mail me.
Just take your time and think...