Thebe is a proper noun, usually referring to a former city in Upper Egypt or a comet in some mythologies, pronounced as two syllables. In most English contexts it is treated as a proper noun with stress on the first syllable, and the consonant cluster is kept cleanly /ˈtiː.bi/ or /ˈθiː.bi/ depending on the speaker. It’s relatively uncommon in everyday speech, so careful articulation and brief vowel clarity are key for recognition.
Full pronunciation guide