CoreData data not showing up in my list view

It looks like inside your CellView your not closing the switch statement, this will probably cause that your Text is only displayed when the checkbox ist checked. (completionState is true) Place your Text that contains your title outside the switch statement:

HStack {
    switch completionState {
    case false:
        Image(systemName: "square")
        
    case true:
        Image(systemName: "checkmark.square")
            .foregroundColor(.green)
    }
    
    Text(title)
        .foregroundColor(.black)
}