시킬 거 돈이 없다 is not only unnatural but grammatically wrong too. It has two nouns 거 and 돈 left unconnected. "-ㄹ + NOUN" is the common, standard form to express "NOUN to VERB", as in "a book to read", "places to go", etc. You can think of common phrases like 읽을 책, 볼 영화, 잠잘 시간, 집을 살 돈, 결혼할 여자, 공부할 교실, etc. This "-ㄹ + NOUN" is however just one of the many adjective forms of verbs. It's good to understand the underlying principle. The verbs can have the following common adjective forms (with examples of 잘되다): ~ㄴ: past, or a result of an action. 잘된 것(something that went well). ~는: present, what is happening now. 잘되는 것(something that is going well). ~ㄹ: future, or what is expected. 잘될 것(something that will go well / something to go well). Note that adjectives take slightly different forms, and that there are others like -던, -ㅆ던, and -ㅆ었던 for verbs (잘되던, 잘되었던, 잘되었었던), but these are more advanced constructs to worry about after mastering the basic ones. Examples: - 너 최근에 본 그 책이 뭐야? What is the book you read recently? - 너 지금 보는 책 있어? Is there a book you are reading now? - 너 비행기에서 볼 책 샀어? Did you buy a book to read on the airplane?

i don't have enough money to order the food. 나는 그 음식을 주문할 충분한 돈이 없다. 시킬 = 시키다 = 주문하다 = order 주문 할 돈이 없다.