I once read, I don't recall where, that Buddha stated that spiritual
enlightenment is not suffering.
This is wrong. Enlightenment is wisdom. The result of wisdom is no suffering. Therefore, wisdom itself & no suffering are not exactly the same thing (although the former leads to the later).
That he put it in a negation on purpose. Ok, I get that, not
This is also wrong. The Buddha said the sole purpose of his spiritual path was complete freedom of mind. (MN 29)
NLP has since been overwhelmingly discredited scientifically but continues to be marketed by some hypnotherapists and by some companies
that organize seminars and workshops on management training for
businesses. There is no scientific evidence supporting the claims
made by NLP advocates and it has been discredited as a pseudoscience
I learned there are 2 types of motivation. 1). Moving away from. 2).
Moving towards to. The second is more valuable in my experience,
because it brings me want I want, instead of something that differs
from what I do not want, but isn't necessarily something I would want
The Buddhist path uses 'moving away' ('abandoning'; 'giving up') to achieve the goal. It is the opposite of what you have written.
Enlightened Buddhist have said: "To be happy, the mind must give up the desire to be happy".
So to be able to move towards experiencing spiritual enlightenment I
need to know what is.
The result of enlightenment is an absence of greed, hatred & delusion. To move towards experiencing enlightenment requires abandoning these very three mental impurities. By moving away from selfish desiring, the mind moves towards what is desired. As Jesus said: "To save one's life, one must lose one's life".
I would like to known, in simple words, what spiritual enlightenment
In Buddhism, most simply, enlightenment is seeing how attachment & self-view is suffering; in such a way that attachment & self-view are given up or dropped by the mind.
So the question is, what is the essence of spiritual enlightenment?
MN 37 most briefly summarises the entire teachings as: "Nothing ought to be attached to (as I, me or mine)". This is the essence of Buddhist enlightenment.