You seem to be a little confused. Easter is dated according to the pagan feast of Astarte, which the "church" calls Easter, all set in place by the 325 A.D. Council of Nicaea, which was convened and presided over by the Roman Emperor Constantine, who is the "beast with two horns like a lamb", who was to "deceive" "those who dwell on the earth" (Revelation 13:11-14). Passover occurs on the 14th of Nissan, and happens on various days of the week, and so happens to fall on Wednesday this year, and according to the chronology, it happened on Wednesday around 2023 years ago.I go to church and pray and meditate on what has been happening (once and eternal salvation) often between Passover Sunday and Easter Sunday. I do the whole Maundy Thursday thing, though I'm not scheduled to get my feet washed this year (but hey, it could happen!). Then Friday I do the veneration of the cross, which I love. Sometimes I also do the stations of the cross. Saturday I pray often as I think about how Jesus was dead that day. Then Sunday (Easter Sunday) is a celebration - a very long church service where we, the congregation,, participate in killing Jesus but then He rises. this is also the day that converts come into the church and are annointed with oil. Then I have a big dinner with family and/or friends. It's an interesting week. What about you?
You might consider Easter the "most sacred day of the year" because when I went to Parochial school in the 1950s, it was taught that if you missed going to church on "Easter", you went to hell. They also taught that all the Protestants went to hell as well.