1.输入该命令按回车键:dnf update -y
2.输入该命令按回车键:dnf install -y centos-release-stream
3.输入该命令按回车键:rpm -q centos-release-stream
4.输入该命令按回车键:dnf install -y centos-release-stream
5.输入该命令按回车键:dnf swap -y centos-{linux,stream}-repos
6.输入该命令按回车键:dnf update -y
7.输入该命令按回车键查看版本:cat /etc/redhat-release