Church?? What is it exactly

People go to "church"  We are told to be a part of our "local" church.  Support your local church, we are told.  There are so many churches.  Some in big buildings with lots of people.  Some in little one room buildings with just a few people.  There are churches who meet outside.  So what does it mean to belong to a church?  Worship together with at least one other person..this makes a church.  Jesus should be the main point / focus/ person of this group of people who are meeting together.  Worshiping our Lord Jesus is done in so many different ways because there are so many different churches.  We are free to worship how ever we want to.   No one should critisize how someone worships unless what they are doing is sinful or it doesnt glorify God and His Son.   So with all this said, it is ok for me to worship with whomever I want to and not feel guilty because I am not attending a big building with lots of people.