The correctness of the doctrine would, of course, be subjective to the doctrinal beliefs of the church seeker. Presuming you are seeking a Christian church, at a minimum, the church should not engage in cult-like behavior (excessive obsession with or control to a dominant personality, excessive exertion of control over members, excessive control over individual finances and giving) and shouldn’t endorse glaringly obvious doctrinal heresy which would exclude the church from inclusion in what is usually considered Christianity.
Again presuming you were looking for a Christian church, I must say my own definition of Christianity is somewhat narrower than what the academic and secular world consider the scope of Christianity. My own definition would include a belief in the divinity of Jesus Christ, that salvation through Him is the sole path to heaven, and that the Bible is the primary doctrinal and spiritual authority. That would place outside my personal view of the spectrum of Christianity a number of belief practices academics frequently include in Christianity, such as Mormonism, Unitarian Universalism, and others.
Then you should seek a church that is a good match for your own doctrinal beliefs. Do you believe in the inerrancy of Scripture? Eternal security of salvation? Predestination or free will? The election of the saved? There are an infinite number of possible doctrinal variants. Ask for their written Statement of Doctrinal Belief (or similar document). If they don’t have one, then I would be concerned they have no doctrinal consistency.
You should also seek a church that is a good match for your personality and provides worship that inspires and motivates you. Are you continually bored in the church? Are the sermons providing you with useful insight?
I believe the most immediate way to recognize a good church is to observe the members. Do they inspire you? Does the Holy Spirit shine through them? Do they model their walk with God and Christ in their daily life, outside of church as well as inside? Are they tangibly different from the fallen world? If they simply seem to be a group of people gathered on Sunday, and not a living part of the body of Christ, they may be spiritually dead or fallen away. Even the best doctrinal match for you is useless if you are not inspired and lead to a closer spiritual path to God.