That is what Passover is a illustration of.
The changes from the Law was because it was fulfilled and in this period of time, (since the Cross) when a person believes in Christ as their personal savior they cease to be either Jew or Gentile, but become one in Christ-Christian.
So, no you don't understand what you are doing, you have rejected your own messiah and returned to the Law which cannot save you!
I would advise you to read the book of Hebrews which was written by Paul to the Jews to explain to them these things.
But God isn't done with the Jews People as a People, since there were unconditional promises made to Abraham (land) and David (ruler) which God will fulfill in the future when He sets up His Millennial Kingdom.
Then all Israel will be saved under the New Covenant (Jer.31, Heb.8)
But right now, without faith in Christ as your personal savior, you are lost and on the way to hell.
Your laws and traditions can't save you, only the Blood of the Lamb can do that.
If there are unfulfilled promises, if there is war and starvation and disease, if there is hatred, lying, stealing and adultery, then the purpose of the Bible has not been fulfilled. As such, we Jews still wait for the Messiah.
Oh, and our guy won’t need a do-over. He will get it right the first time.
The false premises re the Messiah could fill the abyss. The religious establishments and their followers are going to reject him, but $18 on the Jews for ultimate recognition. Kind of too serious a subject to say "pass the popcorn" but... on the shopping list it goes.