Yes you can. You can strive to be better, and of course you will fail by yourself, but this is where God comes in. As you do God's work, God will work though you and help you keep his law. As an example you can take the many monks and nuns who live alone in the desert yet literately soar in a spiritual sense of the world.
As Christ himself said "
Take my yoke upon you, and learn from me, for I am gentle and lowly in heart, and you will find rest for your souls. For my yoke is easy, and my burden is light." The whole point is that faith demands a life that corresponds to that faith. You have to crucify your flesh with your passions and lust, as saint Paul puts it, in order to submit yourself to the Kingdom of God, and the more you struggle in this the more you will take on "the yoke of Christ" and the more he will help you carry it up Golgotha to the Kingdom of God.
Christ had a thing to say about people who claim that simply beliving or being born is enough: "Not everyone who says to me, ‘Lord, Lord,’ will enter the kingdom of heaven, but the one who does the will of my Father who is in heaven.
22 On that day many will say to me, ‘Lord, Lord, did we not prophesy in your name, and cast out demons in your name, and do many mighty works in your name?’
23 And then will I declare to them, ‘I never knew you; depart from me, you workers of lawlessness.’"
Anyway this guy
explains it better than
I ever will