A true Christian will not live a lifestyle of sin continuously according to 1 John 3:6, 9 which says, 6 No one who abides in him keeps on sinning; no one who keeps on sinning has either seen him or known him. 9 No one born of God makes a practice of sinning, for God’s seed abides in him; and he cannot keep on sinning, because he has been born of God.
Basically, what those two verses mean is that a person with the Holy Spirit will repent and stop doing what displeases God. It does not mean that a Christian will never sin again because we are still in our sinful body but, we will always repent and try not to sin again.
A person who claims to have the Holy Spirit and continues to live a life of sin without ever repenting, that person was never saved in the first place and does not have God’s Spirit living inside of them.
Jesus said that those who believe in Him will receive the Holy Spirit and He will never leave them but, will be with them forever.
15 “If you love me, you will keep my commands. 16 And I will ask the Father, and he will give you another Counselor to be with you forever. 17 He is the Spirit of truth. The world is unable to receive him because it doesn’t see him or know him. But you do know him, because he remains with you and will be in you.