It can be tough to choose a program. Students in Israel try out programs for up to a week while still in high school. If you are going to be in Israel six months before a program begins, you can send them an email requesting to try out their program for a few days or a week. Even more so if you are already in Israel.
In regards to learning Hebrew, even the worst student of language can master Hebrew. The author of this website failed Hebrew and nearly failed French and yet now is a fluent Hebrew speaker. All it takes is effort - and being around Hebrew speakers.