Since the law has only a shadow of the good things to come, and not the actual form of those realities, it can never perfect the worshipers by the same sacrifices they continually offer year after year. Otherwise, wouldn’t they have stopped being offered, since the worshipers, once purified, would no longer have any consciousness of sins? But in the sacrifices there is a reminder of sins every year. For it is impossible for the blood of bulls and goats to take away sins.
Therefore, as He was coming into the world, He said:
You did not want sacrifice and offering,
but You prepared a body for Me.
You did not delight
in whole burnt offerings and sin offerings.
Then I said, “See, I have come—
it is written about Me
in the volume of the scroll—
to do Your will, O God!”
After He says above, You did not desire or delight in sacrifices and offerings, whole burnt offerings and sin offerings, (which are offered according to the law), He then says, See, I have come to do Your will. He takes away the first to establish the second. By this will, we have been sanctified through the offering of the body of Jesus Christ once and for all.
(Hebrews 10:1-10 Holman Christian Standard Bible®©)
You have been made holy (set apart) through the sacrifice of Jesus’ life once, and for all. You didn’t earn it, you can’t earn keeping it. It is your new identity. Born of God, you are.
You do need to study, to show that you are approved, and you do need to do the work you are set in place for, as a proper fruit of having repented, to give evidence that your mind is changed by His Spirit. You do not need to fear the lake of fire when you make a mistake, though. Glad that worked out for you…