the old man gave me an advice or some advices last week. which one is the correct option
Neither of those choices is correct.
This is correct ~~> The old man gave me some advice last week.
The old man gave me an advice last week
When determining whether to use "advice" or "advices" in this context, it is important to consider the noun forms. "Advice" is an uncountable noun, meaning it does not have a plural form. Therefore, "advices" is grammatically incorrect.
In your given sentence, it would be correct to say, "The old man gave me advice last week."