what is the strogest reaply to king gambit ?


The position you show is not Kings Gambit, which is 1.e4 e5 2.f4. There are various good responses to this, I like 1.e4 e5 2.f4 exf4 3.Nf3 d5 4.exd5 Nf6 where black develops rapidly. In your position I would probably play d5, but you could also transpose into a Kings Gambit with e5. Probably d6, g6 or e6 are all reasonable moves also.
I think you take the pawn, but not everyone plays 3. Nf3. The other common continuation 3. Bc4 requires some attention, and 3. Qf3 (the Breyer Variation) is quite dangerous, too.

If you're strong enough to play like an engine, then you'll take the pawn and play g5.
But typically KG players don't care if they're technically losing, they just want a big initiative (or just a big mess in general).
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So the "best" reply in the practical sense is usually something else.
But considering the OP can't even post a diagram of the king's gambit, this is all a little too advanced

yes this was my old reaply , the idea is to pervent castling on the king side
but i think black losing tempo becuse he moved the queen twise
and many players casling there any way
