I'm thankful you want to grow in your faith -- because it's the most important thing you'll ever do. God doesn't want us to remain "spiritual infants," tossed about by doubts and falsehoods. Instead, He wants us to grow stronger in our faith -- and one of the most important ways we do this is by being part of a good church.
The first step I urge you to take is to make sure your faith is based solidly on Jesus Christ. In whom is your faith? Only Jesus is worthy of your faith, for He is the Son of God who came down from heaven to save us from our sins. If you have never done so, or if you're uncertain, put your faith and trust in Him. The Bible says, "Salvation is found in no one else, for there is no other name under heaven given to men by which we must be saved" (Acts 4:12).
Then ask God to lead you to a church where you won't only feel comfortable, but you'll be able to grow in your faith. As you visit your friend's church (and perhaps other churches also) ask yourself several questions. Is the Bible central in its preaching and teaching? Is Jesus Christ at the heart of all they do? Are there opportunities for Bible study and service?
As a footnote, if your friend's church isn't known to you, ask others who might know about it. The Internet may also give you information about its denomination, and whether or not it bases its beliefs on God's Word.