If you sure it you want to ,just go for it.
是不对,你从句里边没有谓语,sure是形容词或者副词,不能做谓语的；还有,句子的意思也不通.我觉得应该是这样：If you are sure about it,and that's what you want ,just go for it.
OR
If you are sure (that) that is what you want,just go for it.这里,括号里的that可要可不要.如果要,则它作为后面从句的引导词；如果不要,则是省略了从句的引导词.