I've come across words like 「高級な」、「上品な」、and 「エレガントな」. I'm wondering if any of these can be used or if there are other words. I'm also curious to know if there is a difference between 「高級な」and 「上品な」. Thank you.
高級 usually doesn't describe people, except for referring to higher tier of staff, like 高級官僚 "high-level bureaucrat". エレガント can be used like "elegant" but, as Japanese, it's limited to one's appearance or behavior, rather than inner quality.
I've heard 「上品な」 only as description of products.
On other hand 「高級な」 is literally "high level" and can describe quality of products and social status for example. It is more broader term.
「エレガントな」 is "elegant" and some dictionaries have "elegant" as translation for 「上品な」 and 「高級な」 but I think it is really loose translation. Strictly speaking these words aren't synonymous.