Jesus said He came to fulfill the Law and the Prophets. A fulfillment simply means to FULLY-FILL something. And a fulfillment does NOT change something, rather it makes it COMPLETE.
The Old Covenant laws were incomplete because they provided only temporary solutions for sinful man. But because Jesus was of God and thus eternal, He transformed the physical laws into eternal laws which could save man eternally or completely! For example, when Jesus died on Passover, His sacrifice transformed the physical Passover lamb Sacrifice into an Eternal Passover Lamb Sacrifice. Now, the Israelite no longer needs to keep the physical Passover yearly; rather they only need to keep Jesus in their heart and He will be their Passover Sacrifice Eternally! Likewise, the fulfillment of Tabernacles would replicate or reflect the original, but transform it into an Eternal provision.
The original “Tabernacles” (tents) was a lowly, humble and temporary state for the Israelites as they 
looked forward to their glorious and permanent Home in the Promised Land. In fact, the Israelites were commanded to keep Tabernacles to remember their former humble state. So just as Jesus became the Passover Lamb through His physical Body in order to transform the Passover Lamb into an Eternal Passover Lamb; He also became a lowly “Tabernacle” through His physical Body in order to transform Tabernacles into an Eternal Tabernacles provision. Indeed, we are told that the Son of God took on the lowly, humble and temporary abode of human flesh in order to “Tabernacle” as a man.
“The Word became flesh and made his dwelling (Tabernacle) among us.” John 1:14
The word “dwelling” in this verse means “Tabernacle”. The Apostle John used it to denote the fulfillment of Tabernacles. Moreover, this word is used of Jesus again; but this time as our glorified Eternal Tabernacle:
“Now the dwelling (Tabernacle) of God is with men, and he will live with them” Rev 21:3
Jesus fulfilled Tabernacles when He became a physical Tabernacle but transformed it into an ETERNAL Tabernacle. In other words, Jesus became a physical man in order to transform physical man into an Eternal man! Thus Jesus is our Eternal Tabernacle. Now the Israelite no longer needs to keep the physical Tabernacles yearly; rather they only need to keep Jesus and they will Tabernacle with God Eternally!