1
Sarah is a very specially friend.
Sarah is a very special friend.
Special is an adjective. Use it before a noun or after the verb be: ‘Sarah is a special friend.’ ‘This occasion is very special.’
Specially is an adverb. It often means ‘for a particular purpose’: ‘This cake was specially made for you.’ ‘The room was specially designed for children.’
2
I bought this special for you.
I bought this specially for you.
Use the adverb specially, not the adjective special, to describe why something was done.
Especially normally means ‘particularly’ or ‘more than the others’: ‘I like all fruit, especially strawberries.’
See SPECIAL