Upvote:10
Trinity is a Dogma of the Catholic Church. Hence as with all dogmas a Catholic is bound to believe it in order to maintain the bond of faith.
You have asked: if someone is not 100% comfortable..... Who is this someone? If they are non-baptised person, Catholic church has no official stand regarding them, only God will know.
If they are baptized Catholic then:
One being not comfortable is different from one says he believes Jesus is not God. Your question title and its content differ in its meaning.
If one is not comfortable:
Please remember you don't have to understand a dogma to believe it. So, you can believe in a dogma even if you have doubt. All that is required is your full will, For as long as one remains willing to submit to the Church's decision he remains a Catholic Christian at heart and his wrong beliefs are only transient errors and fleeting opinionsCE : Heresy.
If one says he does not believe in a dogma, and they fully understand the way they are in disagreement with the Catholic Church:
This will make him a Heretic. A person who obstinately persists in heresy will not be in union with the church and hence cannot be saved.