Summoning God Technique is not complicated, the key is to master the Divine Spell. Once you master the Divine Spell, you naturally learn how to use the Summoning God Technique.
As for whether you can summon a Deity, that relies on the skills of the Black Dragon cub. As for the Black Dragon… in this state, Sophia really can't tell if Black Dragon is feigning death or truly dead.
She hopes Black Dragon is faking death, even if she herself was deceived.
If Black Dragon was to resurrect, she would be delighted. As for the Summoning God Technique... if you can't summon a Deity, the divine might of the Summoning God Technique is not even as good as a regular Divine Spell.
"Summoning God Technique and the accompanying Divine Spell, I have taught them all to you, Black Dragon... did I really kill you?"
"Almost, just a breath away, but don't worry, I think I can still save myself in this state."
"You, you're playing dead?!"
"You'll find out soon enough whether I'm playing dead or not."