Christianity is based on who God, Jesus, & The Holy Spirit is.
Quite a few groups, among JW's & LDS offer different teachings on this. This alone is critical. The basics of Christianity has been around since we were first called Christians in the New testament.
Christians believe God, Jesus, & The Holy spirit are all GOD. The trinity concept (which is in the Bible, though the word trinity isn't) is a difficult one to grasp, but yet, the Bible clearly teaches this concept.
The JW's believe that Jesus was created. Christians say no. JW's often quote John 1:1 from their own new world translation (which no other group uses). This verse in their Bible is "In the beginning was the Word, & the Word was with God, & the word was a God".
All other Bibles say, "In the beginning, was the word, & the word was with God, & the word was God".
Vs. 14 goes on to say that Jesus is the word.
Greek scholars from all religious backgrounds, or no religious background at all find this translation to be incorrect, among others I will not get into.
My point being. Anyone can claim to be Christian. Ancient Christian beliefs teach plainly who Jesus, God & the Holy spirit is. Added bonus, it is in the Bible!! One just needs to search the scriptures, with no religious, denomination, or group teaching, & the answer is there. It's easy to take some one's word for it. It's another to actually search & seek like the Bereans did in the New Testament!
Caveat: I am not JW or LDS, but I have spent quite a bit of time with a dear JW, reading through their awake! magazine, & watch tower, along with their version of the Bible. She refused to look at my literature like I looked at hers.....& she would only seek material from her organization.