If Christ conquered sin through resurrection, yet we still sin, and live in a sinful earth, did he really conquer sin? Yes.
From earths creation, man was given choice (Genesis 2:16); it’s one of Gods institutions that survived the fall of man. The resurrection of Christ meant he overcame sin and death (1 Cor. 15:55,57). This didn’t mean that sin was removed from earth or our hearts, it meant Christ gave us a way to escape it. Christ gave us access to God (Ephesians 2:18, Romans 5:2, Hebrews 9:3-5), this allows us a chance to know God, and because of that relationship, overcome sin.
It’s like if your drowning and someone throws you a life saver, just because you have a life saver floating next to you doesn’t mean your no longer drowning, or that because it’s in the water you’ll instantly be saved and on dry land. The life saver means you have a means of salvation where previously you had none. Christ is that life saver.
However you would resent someone trying to shove a life saver over your head if you didn’t recognize your drowning. The same is with most people, they push away Christ because they think they’re on dry land when in fact they’re drowning. In order to use the life saver you need to acknowledge your need for it. God will wait patiently, for you to realize you need him so he can save you.
Just like the logical path that a life saver leads to a boat, so Christ and his salvation lead to God and heavens safety. But God will always give us the choice.