Are Christians still saved if they mix law and grace but believe in the death and resurrection of Jesus Christ?

Some may believe in the necessity of water baptism, observing Sunday rest, speaking in tongues, doing good deeds, or obeying rituals, but, if they trust Christ alone and know that their works don't contribute to salvation, then they are saved. On the other hand, if they believe that certain works are required, in addition to faith, they are mixing faith and works, going against what Paul warns in Gal 3:1-3.

If you are adding works to your faith for salvation, that faith you exercise implies that Christ's death was insufficient, contradicting faith in the gospel. The grace gospel teaches that salvation is solely by God's grace through faith alone, as Eph 2:8-9 states. 

Paul says the following, "Circumcision is nothing, and uncircumcision is nothing, but the keeping of the commandments of God." 1Cor7:19. Similarly, your works are nothing in the light of salvation by grace. Whether you have attempted to work for your salvation or not, know that salvation is available without it and know that your faith should rest in grace alone according to God's command.

Eph.2:8 For by grace are ye saved through faith; and that not of yourselves: it is the gift of God: 9 Not of works, lest any man should boast.

Rom.11:6 And if by grace, then is it no more of works: otherwise grace is no more grace. But if it be of works, then it is no more grace: otherwise work is no more work.