Jesus performed miracles to bless people, to bring glory to God, and to show proof of his claim to be God in human form.
And Jesus’ miracles were recorded for us for a clear purpose: “…that you may believe that Jesus is the Christ, the Son of God, and that believing you may have life in his name.” (John 20:31)
The four gospels (Matthew, Mark, Luke & John) record thirty-five separate miracles that Jesus performed, and he performed many more that weren't recorded. In fact, at the end of John's gospel, John writes that the world would be filled with books if all of Jesus' miracles were written down!