The OP is talking about "salvation" which consists of three stages.
Justification - God totally touches and changes our lives by his grace through faith.
"Therefore, since we have been justified by faith, we have peace with God through our Lord Jesus Christ. 2 Through him we have also obtained access by faith into this grace in which we stand, and we rejoice in hope of the glory of God." Romans 5:1-2
We do not need works at all to be justified. God alone does the "work" of saving us. This is monergism.
"For by grace you have been saved through faith. And this is not your own doing; it is the gift of God, 9 not a result of works, so that no one may boast." Eph. 2:8-9
BUT, Ephesians continues on. And what it tells us, is that the next stage of our salvation, is santification. That means, God continues to work on us through the Holy Spirit, and part of that is doing the works God prepared beforehand.
"For we are God’s handiwork, created in Christ Jesus to do good works, which God prepared in advance for us to do." Eph. 2:10
Sanctification takes the rest of our lives. It is changing us into the image of Christ. That is the transforming effect of Christ on our hearts and lives.
"Do not conform to the pattern of this world, but be transformed by the renewing of your mind. Then you will be able to test and approve what God’s will is – his good, pleasing and perfect will." Romans 12:2
"And we all, who with unveiled faces contemplate the Lord’s glory, are being transformed into his image with ever-increasing glory, which comes from the Lord, who is the Spirit." 2 Cor. 3:18
As this verse above says, we are being transformed into his image, with ever-increasing "glory." That's brings us to the final stage of our salvation - glorification.
"For those whom he foreknew he also predestined to be conformed to the image of his Son, in order that he might be the firstborn among many brothers.30 And those whom he predestined he also called, and those whom he called he also justified, and those whom he justified he also glorified." Romans 8:29-30
"Beloved, we are God's children now, and what we will be has not yet appeared; but we know that when he appears we shall be like him, because we shall see him as he is." 1 John 3:2
And, this verse below explains why we are not made perfect when we are justified by God, at the beginning of our journey with him.
"For now we see in a mirror dimly, but then face to face. Now I know in part; then I shall know fully, even as I have been fully known." 1 Cor. 13:12
So, no, we don't do works to be justified, but we do them after we are saved! And no one is going to lose their salvation, because God gives it. And he will chastize us if we are not following him, obeying his commands and doing the works he has given us to do. And since God doesn't make mistakes about who he chooses, we will accomplish what he has set out for us to do. And one day, he will return, and we will see him face to face, and we will be like him! Hallelujah!