{ مِن شَرِّ مَا خَلَقَ }
According to Ibn Abbas it means Iblees specifically because Allah has not created something which has more evil than him, and because the surah was sent down concerning protecting from sihr, which is completed by the help of Iblees and his forces.
A 2nd opinion is that it refers to Jahannam as if he says, say I seek refuge with the Lord of Jahannam and from the most severe/harsh things which are created in it.
A 3rd opinion that it refers to all categories of harmful animals, eg the predatory animals, which Jinn and humans could also be included in that. Then mentions about scorpians & snakes…
The next point: There is an opinion that this ayah orders RasoolAllah 
to seek refuge with Allah, from Allah. RasoolAllah said: وأعوذ بك منك
I seek refuge with You from You.
It is said that what is meant by that is from what He created from illnesses, sicknesses, witholding of rain, from various types of tests.
Al Jabaa2iy and Al Qadhy claimed that this is a batil tafseer, because Allah’s doing can not be described as “sharr” (not permissible to describe it as such)
They say its defective to say that the one who orders you to seek refuge with Him is the one whom you need to take refuge from.
All of Allah’s doing is from Hikmah and from what is right. So it is not permissable to describe it as sharr/evil
If Allah’s actions were described as sharr(evil), this would mean that Allah would be described as shareer (one who does evil) and He is exalted above that.
And the response: there is no prohbition in saying a3oodhu bika minka and that when somebody suffers for him it is like a sharr, and refered to Allah’s saying:
42:40 The recompense for an injury is an injury equal thereto (in degree)
{ فَمَنِ ٱعْتَدَىٰ عَلَيْكُمْ فَٱعْتَدُواْ عَلَيْهِ بِمِثْلِ مَا ٱعْتَدَىٰ عَلَيْكُمْ }
2:194 If then any one transgresses the prohibition against you, Transgress ye likewise against him
and where difficulties have been described as sharr:
used to say:
meaning I seek refuge with You from the evil of the calamnities/disasters of the night and the day.
The next point:
Some people deviants challenged His saying “qul aoodhu bi rabb il falaq min sharri maa 5alaq” that there is an issue with seeking refuge and with Allahs qadaa2 wa qadr (Allah’s decree and predestination) They are saying how can you be ordered to seek refuge with Allah from his decree when He has ordered it and it wil be reality. They say it is as if Allah says that the thing He decreed for them wil not necessarily happen so seek refuge in Him from it so it wouldn’t happen. And that if it would not have any effect on the qadr that was known, then there wouldnt be any point seeking refuge as you could not defend against it, so there wouldnt be any benefit
the response to this is that:
You are really doing Great, May Allmighty Allah Bless you a lot.