There is one work Jesus did which we cannot and need not do. That is His work of Attonment through crucifiction. Because
Hebrews 10:14 For by a single offering he has perfected for all
time those who are being sanctified.
1. the works I have been doing in John 14:12 refers to all the preaching, teaching, rebuking & miracles that Jesus did. The disciples who beleived in Jesus would also do the same things as Jesus commissions them.
Matthew 10:7-8 King James Version (KJV)
7 And as ye go, preach, saying, The kingdom of heaven is at hand.
8 Heal the sick, cleanse the lepers, raise the dead,
cast out devils: freely ye have received, freely give.
Teaching, baptising & making disciples are mentioned in
Matthew 28:19-20 English Standard Version (ESV)
19 Go therefore and make disciples of all nations, baptizing them
in[a] the name of the Father and of the Son and of the Holy Spirit, 20
teaching them to observe all that I have commanded you. And behold, I
am with you always, to the end of the age.”
I think it also include taking up our cross and living like Jesus did, loving like Jesus did, going through tribulation and experiencing martyrdom.
Matthew 16:24 Then Jesus told his disciples, “If anyone would
come after me, let him deny himself and take up his cross and follow
me.
John 15:13 Greater love has no one than this, that someone lay
down his life for his friends.
Revelation 2:10 Do not fear what you are about to suffer. Behold,
the devil is about to throw some of you into prison, that you may be
tested, and for ten days you will have tribulation. Be faithful unto
death, and I will give you the crown of life.
2. even greater things in John 14:12 - I could give you some clues but not a definite answer
Three more works which Jesus did not do but what the disciples will do are mentioned in
Mark 16:17-18 King James Version (KJV)
17 And these signs shall follow them that believe; In my name shall
they cast out devils; they shall speak with new tongues;
18 They shall take up serpents; and if they drink any deadly thing, it
shall not hurt them; they shall lay hands on the sick, and they shall
recover.
Then we find that during the time of Jesus He prayed for unity among His disciples but up to the last moment there was no unity but competition.
Luke 22:24 A dispute also arose among them, as to which of them
was to be regarded as the greatest.
though Jesus desired & prayed for unity among disciples.
John 17:21 that they may all be one, just as you, Father, are in
me, and I in you, that they also may be in us, so that the world may
believe that you have sent me.
But after the arrival of the Holy Spirit we find that the disciples were united.
Acts 1:14 All these with one accord were devoting themselves to
prayer, together with the women and Mary the mother of Jesus, and his
brothers.
Acts 4:32 Now the full number of those who believed were of one
heart and soul, and no one said that any of the things that belonged
to him was his own, but they had everything in common.
Then nobody died lying to Jesus but we see in Acts 2 people dying for lying to disciples which was considered as lying to God.
Acts 5:1-11 English Standard Version (ESV)
Why is it that you have contrived this deed in your heart? You have
not lied to man but to God.” 5 When Ananias heard these words, he fell down and breathed his last.
9 But Peter said to her, “How is it that you have agreed together to
test the Spirit of the Lord? Behold, the feet of those who have buried your husband are at the door, and they will carry you out.” 10
Immediately she fell down at his feet and breathed her last.
Jesus never pronounced judgement on any man but Peter & Paul ( in some level ) did. Jesus only pronounced "woes".
Acts 8:9-25 English Standard Version (ESV)
20 But Peter said to him, “May your silver perish with you,
because you thought you could obtain the gift of God with money! 21
You have neither part nor lot in this matter, for your heart is not
right before God.
Acts 13:11
And now, behold, the hand of the Lord is upon you, and you will be
blind and unable to see the sun for a time.” Immediately mist and
darkness fell upon him, and he went about seeking people to lead him
by the hand.
Then the whole matter of subjective learning which I answered in Was the power they received in Matthew 10 different from the one they received in Acts 2?