1) "Free of charge" is one way to say you don't have to pay. Sometimes you could say just "free," another word is "gratis," or you could say "for free." In the legal world, sometimes lawyers will work pro bono. And that means for the general good which means they don't charge for their services.
2) "Dependent children" are usually your children living at home until their eighteen as long as they're still in school.
children until the age of 22 , if they're in college, are often counted as dependent children. Sometimes kids though in the US will declare their independence from their parents before they turn eighteen.
3) for life ずっと、一生涯、for good
4) A similar word to "bloated" is "swollen." Bloated sounds like some kind of liquid or gas has been held inside. Swollen especially when you talk about people tends to mean because of some kind of injury or something that's not quite healthy.
5) wellness mental health, physical health も入れた総合的な 健康状態 "Wellness" is the word that sounds a little bit fashionable to me,
meaning because you could say you're well, you're healthy, you're not sick , why do we need the word "wellness?" I'd say the way it's been used now it tends to focus on not just being healthy, but also working a little bit to stay healthy, taking care of yourself eating right, exercising a bit, and also making sure you're mentally healthy. You're rather
6) an instant success すぐさま成功を収めた、an overnight success
7) Instead of "regulatory roadblocks," you could say "regulations," or "requirements," or you could add government to that to show they're quite official. Some people when they talk about very negatively might call it government meddling, meaning they're missing around in places where they shouldn't be.