Welcome in the forum and in the fascinating world of PSoCs.
The LUT component for PSoC3/4 and 5 is like a PLD: you specify how many inputs and outputs you want to have and then you provide the bit-pattern for each input-combination to appear at the outputs. Have a look at the datasheet in your preferred language.
When you already installed Cypress Creator (3.2 is latest version) you may right-click on the component and see the datasheet directly.
I just realize that you are using Creator 2 which is a rather outdated version. When you use that only because your PSoC3 chip is not supported by the newer versions (3.2 is the actual one) I would strongly suggest you to upgrade your hardware, preferrably to a PSoC5 version (same price). When you cannot spend that much money (Your name shows you're a student) another choice would be to get hands on a PSoC4-M Pioneer kit which is a bit reduced in price and of course in capabilities, too (no display).
thank you for your quick answer. I think I will upgrade my hardware. This should be the best way, because than I can use the wavedac8 component which is able to create sine waves without any additional work of mine.
It is not the LUT component being used in wavedac, it is a look up table, array,
of sample values for the sine, or whatever wavefom you will be using.
In the example project that table is already defined in code and filled with values.