I am adopted from China but I don t think I m fully Chinese?

What is "fully Asian"? Israeli? Timorese? Yemeni? Sri Lankan? All are "fully Asian" as are people from about forty other countries. While Chinese people are Asian, most Asians are not Chinese so why call yourself "Asian"? Asians come in all shapes and sizes and with every possible shade of skin and hair colour. Some Asians have epicanthic folds in their eyelids, many do not.

China is the almost the size of Europe and has more people. There is as wide a variation in appearance among people of China as there is among people of Europe. China borders North Korea, Russia, Mongolia, Kazakhstan, Kyrgyzstan, Tajikistan, Afghanistan, Pakistan, India, Nepal, Bhutan, Burma, Laos and Vietnam and Chinese people resemble their neighbours in those border areas.

No one can tell you for sure. There is normal variation in all races, so just because you don't look like the typical Chinese person doesn't mean you aren't full Chinese.

You should ask your parents maybe? I honestly can't tell you much without knowing more information. Maybe they will know more.

I wouldn't worry about it too much regardless.