It is actually the wrong question to start with. Church is not a venue or an event that you attend. Church is the people of God. You don’t attend a church, you are part of the church. If you belong to Jesus then you belong to his family meaning that you are a member of the world wide and historic church. Your membership of The Church is reflected in and demonstrated by your membership of a local church.
A faithful follower of Jesus is a disciple. Jesus in his Great Commission called us to make disciples, baptising them and teaching them to obey everything he had commanded. Jesus’ teaching includes the command to love one another -this is how others know that we are his disciples. Jesus says that where two or three are gathered he is present with them. In Matthew 18 Jesus describes the role of the church family together in exercising discipline and encouraging repentance, forgiveness and restoration. Jesus said that he will build his church.
The Church is the bride of Christ (cf Ephesians 5:21-32). Can you really love him without loving and honouring his bride?
1 Corinthians 12 shows that we are part of the body, we are connected together. Hebrews encourages us to gather together for mutual encouragement and to be spurred on in following Jesus. Hebrews 10:25 exhorts us to keep meeting together and not to cease in this. The writer notes that some have stopped gathering and urges his readers not to be like them. Meanwhile, John says that those who have broken away and divided from the body show that they never really belonged in the first place (1 John 2:19).
You can trace through Scriptures a Biblical Theology theme that shows people turning away from God’s word and being exiled/scattered. Adam and Eve are exiled from Canaan. The people at Babel are scattered because of idolatry. Israel are exiled from the land. God’s aim is to restore a people to himself reconciling us through the Cross. The result is that we are also reconciled to each other. God’s plan is to gather a people from every nation to worship him. This is seen in Genesis 12 where God promises Abraham that he will make him into a great nation. A big theme in Deuteronomy is that God calls his people to gather and assemble before him. The prophets promise a day when people will be gathered into the holy City and to the Temple to praise God. Acts 2 gives us a foretaste of that great gathering at Pentecost. The Book of Revelation points forward to that great day when people from every tribe and tongue will worship him.