I'm an 18-year-old ,who is a girl from xxCity,xxProvince,China.应该为
I'm an 18-year-old girl who is from xxCity ,xxProvince in China.
I am totally fall in love with it and your excellent performance 中去掉am,fall改为 fell,
At this time of "the" Spring Festival
to greeting each other中greeting应改为greet
may you success 改为may you succeed或may you make success
英语信件中一般不用farewell.多用些祝福的话语,如Best wishes!等、