Sympathique in French, sympathisch in German, sympatický in Czech; the word has spread in some form probably to all European languages, with one major exception—English. That’s right, “sympathic” is not an English word, as a quick search in any respectable dictionary tells you.
So how do you translate “sympathic” (I’ll use this word to refer to its meaning in other languages) into English when there is no such word? The fact is: you don’t. There’s no direct English equivalent for what “sympathic” is expected to mean by speakers of other languages, so you will have to work with words like “nice”, “kind”, “likeable”, etc.:
You can also use the word “like” if you find somebody “sympathic”:
There is one word that has a meaning similar to “sympathic”: congenial. Unlike “sympathic”, “congenial” is a fairly formal word and using it in everyday conversation could make you sound pretentious, so I advise against using it unless you know what you are doing.
So far, so good, but there is one more trap many learners fall into. In English, there is a word “sympathetic”, which means “compassionate to someone or approving of something”, but not “sympathic”: