As far as I can gather from the official LDS website links here, this is what they believe about Jesus:
https://www.lds.org/scriptures/gs/god-godhead?lang=eng&letter=g
Father in Heaven: The Father of the spirits of all mankind. Jesus is his Only Begotten Son in the flesh. Man has been commanded to obey and give reverence to the Father and to pray to him in Jesus’ name.
God the Son: The God known as Jehovah [in the O.T.] is the Son, Jesus Christ… he is the eldest of the spirit children of Elohim [who is not the same deity as the one known in the Bible as Jehovah]… it was actually Jesus who was the Creator under the direction of God the Father [Elohim].
Jesus Christ: https://www.lds.org/scriptures/gs/jesus-christ?lang=eng
Jehovah: https://www.lds.org/scriptures/gs/jehovah?lang=eng&letter=j
They say the name ‘Jehovah’ denotes “the eternal I AM.” Jehovah is said to be the premortal Jesus Christ and came to earth as a son of Mary (Mosiah 3:8; 15:1; 3 Ne. 15:1–5).
Michael the Archangel: https://www.lds.org/scriptures/gs/michael?lang=eng&letter=m
The name by which Adam was known in the premortal life. He is called the Archangel. In Hebrew the name means “Who is like God.”
Adam: https://www.lds.org/scriptures/gs/adam?lang=eng&letter=a Adam is the Ancient of Days and is also known as Michael (Dan. 7; D&C 27:11; 107:53–54; 116; 138:38). He is the Archangel and will come again to the earth as the patriarch of the human family, preparatory to the second coming of Jesus Christ (D&C 29:26).
They seem to teach that it was Michael who was put on earth as Adam, and Michael was one of three gods who created this planet. Adam is said to be the incarnation of a god who is ‘related’ to man. Brigham Young said on April 9, 1852
“When our father Adam came into the Garden of Eden, he came into it
with a celestial body, and brought Eve, one of his wives, with him. He
helped to make and organize this world. He is Michael, the Archangel,
the Ancient of Days about whom holy men have spoken – He is our Father
and our God, and the only God with whom we have to do… the earth was
organized by three distinct characters, namely Elohim, Jehovah and
Michael, these three forming a quorum… (Journal of Discourses
1:50-51).
It is essential to grasp this, prior to reading the Temple endowment ritual where three LDS priests represent Elohim, Jehovah and Michael, for they depict Jehovah and Elohim to be separate beings; Michael to be a god; Michael made incarnate in the person of Adam, thus, Adam is a god incarnate.
Their teaching about Adam has a direct bearing on their Christology as they claim that Jesus was the natural born child of Adam and Mary:
“When the Virgin Mary conceived the child Jesus… he was not begotten
by the Holy Ghost. And who is his Father? He is the first of the human
family. Jesus our elder brother, was begotten in the flesh by the same
character that was in the garden of Eden.” (Young, in Journal of
Discourses 1:50-51)
As Adam is believed by them to be a god incarnate, then this god is said to have had sex with Mary, to produce Jesus in the flesh. Their doctrine of pre-mortal existence is needed to make sense of this, but I do not want to digress by launching into that.
Summary: This answers your question, ‘Was Jesus created?’ with an emphatic ‘Yes’.
As for your question, ‘Is Jesus part of the One Being of God?’ it is difficult to answer because LDS Christology has more than one Being of God. As has been shown from their quotes, Elohim existed before Jehovah did; the Archangel Michael is also said to be a god, as is Adam. I can only suggest that the Trinitarian phrase, “the One Being of God” has no place in LDS theology as they have more than one God. “The One Being of God” in Christianity is one Being who subsists in three uncreated, co-equal persons. That is not the LDS understanding although they would say Jesus is “part of” God’s Being! Just not in the Trinitarian sense.
The answer to your question, ‘When Jesus came to earth, was he God incarnate?’ requires knowing what God the LDS speak of here. They say Jesus was the God Jehovah in his pre-mortal existence, so that Jehovah incarnated in the human form of Jesus. Yet because they do not take Jehovah to be the only true God of the Bible, this is seen to be at odds with Trinitarian doctrine.
The answer to your last question, “Was Jesus resurrected as a spirit creature or did he ascend into heaven with a physical body?” appears to be that Jesus has a resurrected physical body, according to their scripture in Alma 11:42-43. Verse 43 speaks of the general resurrection of the dead, saying, “The spirit and the body shall be reunited again in its perfect form, both limb and joint shall be restored to its proper frame, even as we now are at this time.” As Jesus’ resurrection is the ‘template’ for all other human resurrections, it would appear that this also applies to his resurrection.