I believe in an Almighty God. He has all power, He knows everything, and He is present everywhere at once.
He does listen to prayers, He tells us to pray for the things we need. And He answers prayers. But His answers are not always yes. Sometimes He says no.
But you must pray with faith, believing that God hears you and He will answer you.
The bible does say that God doesn't answer some prayers because of our motives and the condition of our hearts when we ask.
From personal experience I will tell you that God has answered many, many prayers for me. Some of them have been in critical situations, some prayers have been borne in moments of despare, some have been for things I wanted but didn't qualify as a need, some have been for physical healing, and many have been for other people's needs.
And God has ALWAYS been faithful, answering prayers, changing my heart, helping me forgive, blessing me, and sometimes showing me that what I wanted wasn't what was best in a particular situation.
Recently I was in a situation that there was really no way for me to succeed. Those with the power in the situation had decided they didn't want me to succeed and had set it up so that I couldn't. It was virtually airtight.
I suspect it wasn't personal, there may have been another reason they were doing this, I may have been collatoral damage.
So I started praying about it. Over and over again, everyday, sometimes multiple times a day. And I did what I knew was right even when I REALLY, REALLY wanted to do otherwise.
The Lord blessed me and gave me wisdom. I came through the situation successfully. No one would have thought that was possible. I know it was only the hand of God that guided me through a mined path and I am so thankful.