보쟝 is a childish cute form of 보자. More examples https://www.italki.com/question/314051

보장 is a hanja word (noun) unrelated to 보다. It means a guarantee or assurance with a promise, often a formal one by a product seller, between institutions or nations. 보장하다 (to guarantee). 보장되다 (to be guaranteed), 보장(을) 받다 (receive a guarantee/assurance) are the verbs. * 품질 보장 = guarantee of product quality. (보증, "guaranteed like certified", is also used) * 최저가 보장 = lowest price guarantee. * 유엔 안전보장이사회 = United Nations Security Council. * "걱정하지 마. 잘될 거라고 내가 보장할게. = Don't worry. I guarantee/assure you it will go well.