A 'type' does not mean 'the same' or 'identical'.
OT type: sins "covered" by water once a year which brought their sins to their conscience [remembrance] each year [Hebrews 10:3]
NT antitype: saved by 'living water' ONCE AND FOR ALL [Hebrews 7:27] John 4:10,11 - Jesus answered and said unto her, If thou knewest the gift of God, and who it is that saith to thee, Give me to drink; thou wouldest have asked of him, and he would have given thee living water. The woman saith unto him, Sir, thou hast nothing to draw with, and the well is deep: from whence then hast thou that living water?
John 7:37-39 In the last day, that great day of the feast, Jesus stood and cried saying, If any man thirst, let him come unto me, and drink. He that believeth on me, as the scripture hath said, out of his belly shall flow rivers of living water. (But this spake he of the Spirit, which they that believe on him should receive:; for the holy Spirit was not yet given; because that Jesus was not yet glorified.)
Well, how were those 8 souls - 8 people saved? They were saved from the flood because they believed God and got on the ark. The Israelites believed God and walked through the 'walls' of the Red Sea. These both are symbolic of baptism - not as a ritual cleansing from sin but being saved as in passing from the old to the new.
Yep water is used as the OT type - a type of what was to come - they were saved from destruction by water - we are saved by "living water" which represents the holy Spirit. Water does not 'create' that new creation' within a person - it is 'born' by the Spirit.
It is impossible to please God in the flesh - so the washing of the filth of the flesh does no one any good. We must be cleansed from the inside out - the new birth; that new creation within the born again believer ONLY is what makes us children of God. It is that spirit within us that 'makes us perfect in every good work to do his will, working in us that which is wellpleasing in his sight through Jesus Christ' - all this can ONLY be done via the holy Spirit; the washing of water cannot do this.
Repent and be baptized in the name of Jesus Christ - water or Spirit? What baptism does Jesus Christ baptize with/in? The only way to have a good conscience toward God is to know who we are IN Christ Jesus. To know that he dwells within us via the holy Spirit, via the new birth. It is making Jesus our Lord, being baptized in the Spirit that makes us Christians - not any church we attend, being baptized in water, or doing good works that make us a Christian - unbelievers can do all these things. What makes us a Christian is being born again of the Spirit - and to be born again of the Spirit is to be cleansed with 'living water' given by Jesus Christ. How can dunking in water create that new creation in Christ within you? All it can do is symbolize something - it was and is a 'type' of the true baptism with and in 'living water' which is the holy Spirit.