John 3:16 doesn't say everyone, just whosoever. There is a big difference. And, God is still in charge of how His Universe works, regardless of how man wants it to work. If God elects a person for salvation, that person will fit into John 3:16 and Whosoever. Mankind is still responsible as he or she was born into sin and will continue in sin unless God calls that person to salvation. God doesn't condemn a person needlessly. He does save those whom He wishes. God has that prerogative.
Romans
9:14 What shall we say then? Is there unrighteousness with God? God
forbid.
9:15 For he saith to Moses, I will have mercy on whom I will have
mercy, and I will have compassion on whom I will have
compassion.
9:16 So then it is not of him that willeth, nor of him that runneth, but of
God that sheweth mercy.
9:17 For the scripture saith unto Pharaoh, Even for this same purpose
have I raised thee up, that I might shew my power in thee, and that
my name might be declared throughout all the earth.
9:18 Therefore hath he mercy on whom he will have mercy, and whom
he will he hardeneth.
9:19 Thou wilt say then unto me, Why doth he yet find fault? For who
hath resisted his will?
9:20 Nay but, O man, who art thou that repliest against God? Shall the
thing formed say to him that formed it, Why hast thou made me
thus?
9:21 Hath not the potter power over the clay, of the same lump to make
one vessel unto honor, and another unto dishonor?
9:22 What if God, willing to shew his wrath, and to make his power
known, endured with much longsuffering the vessels of wrath fitted
to destruction:
9:23 And that he might make known the riches of his glory on the
vessels of mercy, which he had afore prepared unto glory,
9:24 Even us, whom he hath called, not of the Jews only, but also of the
Gentiles?
9:25 As he saith also in Osee, I will call them my people, which were not
my people; and her beloved, which was not beloved.
