Repentance of the sins we know of is the first part of exercising faith in Christ, but obtaining forgiveness of one’s sin is not the end of the journey. It is merely the beginning:
17 ...the gate by which ye should enter is repentance and baptism by water; and then cometh a remission of your sins by fire and by the Holy Ghost.
18 And then are ye in this strait and narrow path which leads to eternal life; yea, ye have entered in by the gate; ye have done according to the commandments of the Father and the Son; and ye have received the Holy Ghost, which witnesses of the Father and the Son, unto the fulfilling of the promise which he hath made, that if ye entered in by the way ye should receive. (2 Nephi 31)
Forgiveness of sins makes possible the reception of the Holy Ghost, which is the mechanism through which the Father successively reveals everything you yet lack to become like him, commensurate with the degree of faith you exercise.
Obtaining the Holy Ghost enables you to enter into the lifelong path of learning more from God line upon line:
15 And I heard a voice from the Father, saying: Yea, the words of my Beloved are true and faithful. He that endureth to the end, the same shall be saved.
16 And now, my beloved brethren, I know by this that unless a man shall endure to the end, in following the example of the Son of the living God, he cannot be saved.
17 Wherefore, do the things which I have told you I have seen that your Lord and your Redeemer should do; for, for this cause have they been shown unto me....
19 And now, my beloved brethren, after ye have gotten into this strait and narrow path, I would ask if all is done? Behold, I say unto you, Nay; for ye have not come thus far save it were by the word of Christ with unshaken faith in him, relying wholly upon the merits of him who is mighty to save.
20 Wherefore, ye must press forward with a steadfastness in Christ, having a perfect brightness of hope, and a love of God and of all men. Wherefore, if ye shall press forward, feasting upon the word of Christ, and endure to the end, behold, thus saith the Father: Ye shall have eternal life.
21 And now, behold, my beloved brethren, this is the way; and there is none other way nor name given under heaven whereby man can be saved in the kingdom of God. And now, behold, this is the doctrine of Christ, and the only and true doctrine of the Father, and of the Son, and of the Holy Ghost, which is one God, without end. Amen. (2 Nephi 31)
There is a difference between being forgiven of past sins and being holy. Forgiveness of past sins comes as you forsake those sins and reconcile yourself to what you presently know about God. Being holy goes beyond reconciling to what you presently know about God. You become holy as you become more like God is , not just how you presently believe him to be. Becoming holy requires learning more about God and assimilating everything you learn about him into your own character.
There is no other way to obtain eternal life except through a lifetime of learning more about God and unfailingly implementing it.