Is this a good first paragraph for an essay?

I would give it a C minus. First of all, never start an essay with "hello". Also, you say the assignment is to describe physical characteristics, but instead you write mostly about your personality and preferences, not your physical characteristic.

Here is a sample paragraph:

"If Hollywood was casting an all American boy character, they would pick someone who looks like me. I am a 14 year old with sandy brown hair and hazel eyes. I am tanned and in good shape from my outdoor activities. I have a fit, wiry runner's body and at 5'4" tall I am still growing. I tend to choose clothes that are understated and casual; my clothes are clean, but not fancy. I am quick with a friendly smile that shows one slightly crooked front tooth."

B- good

I am a 14 year old boy, whose name is Flare. I am active outside during the day. ; I spend some time practicing tennis with my friends during the summer and spring. I don’t care what I wear - clean or not - but not too noticeable. . I am friendly to people even if it doesn't go my way , because I wouldn't like to cause a fight, but if the argument is unbearable then I would have to disagree.

Physical characteristics need to include appearance, height, weight, etc

https://www.google.ca/search?sourceid=navclient&ie...

The first thing I noticed was don't forget to capitalize your name. You are important, and your name should be capitalized! I am guessing that English is a second language?

I see some translation issues- and I was not sure if this is an issue for your paper. For example- the way I would have worded it would be:

"Hello, my name is Flare Le. I am an active 14 year old boy, who plays outside during the day. In the summer and spring, I practice tennis with my friends. ..... do you see the difference?