"Did you receive the Spirit by the works of the law or the hearing of faith?" (Galatians 3:2). Scripture makes it clear. The Holy Spirit is not earned by the works of the law. You received the Holy Spirit as the gift of God, through faith in the Lord Jesus Christ (Gal. 3:13-14).
Believers in the Lord Jesus Christ receive the Holy Spirit. Several Bible passages teach that the Holy Spirit is given to all believers, rather than to a select few (John 7:37-39; Acts 11:16-17; Romans 5:5; 1 Corinthians 2:12; 2 Corinthians 5:5). The gift of the Holy Spirit is not a reward, and no merit is ever involved in receiving a gift.
All believers received the gift of the Holy Spirit. That means the Holy Spirit is not just working in some believers, but in all. You cannot be a Christian without the indwelling Holy Spirit, also known as the Spirit of Christ (Romans 8:9; 1 Corinthians 12:3). The Holy Spirit seals every believer (Ephesians 1:13). The Holy Spirit is within every believer now.
The indwelling Holy Spirit is Christ living in you as a believer. The Holy Spirit comes only and always as the gift of God to all believers. The Holy Spirit enables the believer to live the Christian life. No believer can merit nor earn the indwelling Spirit.