Is it permissible to travel to Indonesia to build a mosque, lead congregational prayers, teach the Qur'an by heart, and teach the Arabic language, knowing that I have not memorized the entire Qur'an and have not studied under a shaykh?

Whoever wishes to undertake the call to Allah must be sincere to Allah, arm themselves with beneficial knowledge by seeking out a proficient shaykh, frequently read the books of trustworthy scholars, strive to memorize the Quran, speak only about what they know, not be ashamed to say "Allah knows best" regarding what they do not know, and adorn themselves with good character.