Can the Dhamma Teaching be
given in short?

Yes! The Blessed Buddha once instructed his son
Rāhula in this very way:
Having left behind desire for the five streams of simple sensual pleasure,
captivating forms, satisfying the mind, having gone forth from the house in
faith, put an end to suffering!
Cultivate Noble friends, an isolated lodging,
which is remote,
secluded, silent, and with little traffic. Be moderate in eating!
Do never crave neither for fine
robes, or foods, nor requisites, or lodging!
Do not
ever return to the worldly life again. Be fully controlled regarding
the monastic discipline, and the 5 sense abilities. Be completely
and constantly
aware of the body as a frame of bones, skin, and flesh. By disgusted with
all in
this world. Avoid beautiful objects, which
provokes lust. Make mind one-pointed,
concentrated, absorbed, well focused on non-attractiveness. Develop
then the
signless mind. Cast out any latent tendency to the conceit:
"I
am"! Then by fully
understanding self-deception you will wander & dwell stilled,
in perfect peace...
Sutta
Nipāta 337-342

On Buddha's
son Rāhula,
who was the most intent on the training (sikkhākāmānam):
https://What-Buddha-Said.net/library/DPPN/r/raahula.htm
He awakened in the
Andhavana forest, when hearing
the Cūla Rāhulovāda
Sutta:
https://What-Buddha-Said.net/library/ati_website/html/tipitaka/mn/mn.147.than.html
