您可以在这里看到创建命令的各种方法。https://docs.microsoft.com/en-us/dotnet/api/system.data.sqlclient.sqlcommand.-ctor?view=dotnet-plat-ext-3.1
您应该使用using…end using块，这样您的连接和命令将被关闭和释放，但是您需要在使用这些对象的本地方法中使用它们。
我不得不猜测数据库中字段的类型和大小。检查数据库并相应地更正代码。

Public Sub InsertPackageDetails(ByVal PackageName As String, ByVal PackageDescription As String, ByVal DateOfInstallation As DateTime, ByVal ImportPackageStatus As String)
    Dim SQL As String = "Insert into PackageInstallation(PackageName,PackageDescription,DateOfInstallation,ImportPackageStatus) 
                          Values(@PackageName, @PackageDescription, @DateOfInstallation, @ImportPackageStatus;"
    Using cn As New SqlConnection("Your connection string"),
            cmd As New SqlCommand(SQL, cn)
        With cmd.Parameters
            .Add("@PackageName", SqlDbType.VarChar, 100).Value = PackageName
            .Add("@PackageDescription", SqlDbType.VarChar, 100).Value = PackageDescription
            .Add("@DateOfInstallation", SqlDbType.DateTime).Value = DateOfInstallation
            .Add("@ImportPackageStatus", SqlDbType.VarChar, 100).Value = ImportPackageStatus
        End With
        cn.Open()
        cmd.ExecuteNonQuery()
    End Using
End Sub