Salam Lisiane: Here is the difference between البارحة/ أمس: البارحة: means last night, so it only refers to the night part of yesterday: (ليلة البارحة). أمس: means the whole day yesterday, including its day and night. Now regarding the difference between سنة and عام, they were mentioned in Qura'an Associated with different things, even though both mean "year": سنة: was associated with hard times. عام: was associated with good times.

أنّ العام يُستعمل لما فيه خير والسنة لما فيه شر.

In classical Arabic "سنة " is used to refer to a difficult year ( drought, starvation, ...) and "عام" is used to refer to a year of abundance. But nowadays most people don't make difference between them

"سنة" و "عام" لا يوجد اي فرق بينهما الكلمة "امس" يتحدثونها في اللغة العربية الفصحى فقط اما "بارحة" او "امبارح" تعتبر كلمة عامية ولكن معناهما واحد

actuality no difference