If the IRGC really wants to fight this war seriously, then they need to define what are their primary goals in this war, just like the Zionists did so for the 12-Day War.
Iran can't just simply accept a ceasefire just when the enemy who started this war suddenly wants peace negotiations when they're starting to lose a few hundred soldiers after bombings killed thousands of soldiers and civilians inside Iran.
To restore deterrence, Iran needs to define its goals? For example :
1. Internally, Iran may decide not to accept any ceasefire until a major strategic goal has been achieved ( like the sinking of a US Carrier or something)
2. Or Iran won't stop until all US bases are destroyed, or Iran devastates Israel enough to a certain degree
3. Iran needs to totally rout the enemy so much that they won't even think of going to war with Iran again. Treat this as an existential war, in which victory would only be considered if after the war, the enemy becomes so weakened or "learned their lesson" that they have to sign at least a 50-year or 100-year Peace Treaty/Non-Aggression Treaty with Iran to secure the Peace for many decades to come so Iran can rebuild and re-develop peacefully without any chance of this shit happening again.
So, Iran must treat this seriously now and no longer play-play...