''She bought me a nice dress'' OR ''She bought for me a nice dress'
1.'What will be appropriate to say?
''She buys me new clothes''
2.Is it right to say clothes in place of ''dress''?
You should say 'She bought me a nice dress'.
You could also say, 'She bought a nice dress for me'.
You can use clothes instead of dress but clothes is uncountable.
Your sentence 'She buys me new clothes' is grammatically correct but it doesn't seem quite complete to me. I would prefer something like: 'She buys me new clothes when I need them' or 'She buys me new clothes all the time' but I think yours is acceptable.
You can also say 'She bought me some nice clothes'