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For it is by grace you have been saved, through faith—and this is not from yourselves, it is the gift of God— not by works, so that no one can boast. For we are God’s handiwork, created in Christ Jesus to do good works, which God prepared in advance for us to do.
Ephesians 2:8‭-‬10 NIV
https://bible.com/bible/111/eph.2.8-10.NIV

1. Grace as what Merriam-Webster dictionary defines is the "unmerited divine assistance given to humans for their regeneration or sanctification".
2. The verse tells us that God freely gives the salvation of man through His grace, not by the merit of man.
3. That salvation is a gift from God. As we know, a gift is something that requires no payment in return. It is completely free. It is something freely and willfully given.
4. The last phrases in the verse say "-not by works so that no one can boast." It is not because of the efforts of man that he is saved, but because of the work of God. I could say, that if a man thinks that what he does is the measure of the assurance of his own salvation, there is a tendency that he will boast because of it. And He will not acknowledge God for his salvation, but only to himself.
5. The first phrase in verse 10 says "for we are God's handiwork, created in Christ Jesus to do good works". We are a work of God. And a work of God is created in Christ Jesus to do good works. In simple terms, we are an "ongoing" project of God.
6. Faith is an action word. It is acknowledging that someone or something is true and believe it to be true, and you act on what you acknowledge and you believe that is true. There is a great level of sureness and certainty in faith. (Hebrews 11:1) True faith will result in good works!

Grace is an unmerited divine assistance of God given to us. Faith is the strong belief in God, His existence and His being. Faith is an "action word." True faith will result in good works.

Grace from God + response of man through faith = Salvation
Salvation is totally free, it is a gift from God.

Will you respond to God's gift?