Why HTTP use TCP connection ?

Because TCP sends the data in order. Otherwise images and text would be where ever happens and websites would be just a big mess.

Because TCP is connection oriented means it provide acknowledgement, so it send data with sequence, TCP provide guarantee, so sender know that our data is successful received by receiver, so we use TCP.

because tcp is loss free and you don‘t need the speed of utp

because TCP is connection protocol. it uses 3 way handshaking. it is reliable. now-a-days we have http 1.1 which is persistent. so TCP is better option for it. hope that helps.