Jehovas Witnesses don't believe that he is God. They also don't believe in the trinity, at least in the sense that other xtians do.
John 1:1 states "In the beginning was the Word, and the Word was with God, and the Word was God."
They believe that "the word" was gods very first creation in heaven before he created earth or the universe. The Word was god in the sense that it was made from the same "makeup" as god, but it was a part of god that he had separated from himself. And it was through The Word that god created everything. The word had the appointed task of creating everything, but everything that The Word does is Gods will. It was through The Word that God created The earth and the universe and everything we know. The Word is the only thing that god himself created. Jesus, was The Word embodied in human form. This is what is meant when Xtians say that god sent his only begotten son to earth. Jesus had already existed in heaven since the beginning of time. He did not become aware of his pre earthly existence until he was baptized by John the Baptist.
So when they (Jehovahs Witnesses) speak of "The father", they are talking about God himself. When they speak of "The Son", they are speaking of "The Word" who took human form on earth as the man Jesus.
Now on to The Holy Spirit.
The Holy Spirit is a slightly more difficult concept. God himself resides in heaven. He does not himself enter the universe or come to earth. The Holy Spirit is, as JWs call it, "Gods active force on earth. What this means is a few things. The Holy spirit is kind of like a spark of God, or a tiny piece that inhabits all living things on earth. Imagine a toaster. On its own, when it is not plugged in, it serves no purpose. It cannot make toast. But when you plug it into the socket, it now has some electricity flowing in it and it can serve a purpose. The electricity in the toaster is kind of like the holy spirit. It inhabits all of us and is what gives us life. It is also what compels us to do good deeds. So when good things happen on earth, it is "Gods
active force on earth.
The holy spirit is also what god uses to talk directly to humans on earth. When Moses was on Mt. Sinai receiving the 10 commandments from god, and carved them into the side of the mountain, it was "Gods active force", or The Holy Spirit on earth. And when Moses asked to see god, and God said that if Moses were to see gods face, he would surely die, so god allowed Moses to see gods backside, well, that was actually The Holy Spirit that Moses saw.
This, mind you, is what Jehovah's Witnesses believe about Jesus, and the trinity. They do not believe that god is a "triune" god, and point out that many pagans believed in Triune gods. So the idea of a trinity is pagan in origin. JWs do not use the word trinity. The use the words "God", "The Word/Jesus" and "Gods active force/The Holy Spirit"
Jehovas Witnesses do not call themselves "Christians", because they believe that Worship should only go to god. I don't know the exact passage, but there is somewhere in the gospels where a man bows down to pray to Jesus and Jesus lifts him up and says "Do not pray to me, but pray to him who sent me [God]".
So JWs do not pray to Jesus, or saints, or relatives or Mary or anybody except God. They see Jesus as the messenger of Gods word.
Imagine it this way, lets say That I am a billionaire, and I know of a village that is completely destitute. I want to help this village but I cannot go there, so I send you with a few million dollars to help them. You bring them the money and tell them it is from me. Now, sure they are appreciative to you for bringing this money, but it was from me. JWs see praying to Jesus as thanking the person who brought the money to them as if it was his own rather than the one who sent it in the first place.
Other Xtians don't really see JWs as "Christians", but they largely don't know what to think of them. JWs tend to call other Christians by their individual denomination, i.e. Catholic, Lutheran, Baptist etc. And they refer to the whole of "Christianity" as "Christendom", or "The kingdom of Christendom".
So, JWs highly rever Jesus, and follow his teachings, but do not worship him.
So, hope that wasn't too much to read.