what is the meaning of TCP protocol is a connection oriented [duplicate]

        I read some of Wikipedia pages about computer networks and learned how and why they evolved.

about TCP and IP i learned that for reducing complexity of network, the intelligence in the network is purposely located in the end nodes. so IP protocol and all devices that work in level 3 of OSI model are unreliable(there’s no way to handle data corruption, packet loss, duplication) and connection less (packets for same source may path different nodes to rich the destination host).

so the upper layer protocols of IP are responsible for resolving these issues. for example for ensure that the packets are in correct order, we can buffer network data.

my questions is how we can have a connection oriented protocol (TCP) over a connection less protocol(IP)? the packets Have passed through routers and reached the endpoint(each packet routed individually), how TCP provides a virtual circuit communication channel in this point of time?