Indeed, pasta bolognese, as well as many kinds of cheeses and other dishes were minvented there. Indeed, pasta bolognese, as well as many kinds of cheeses and other dishes were invented there.

'Minted' is quite uncommon in English - it would make more sense in this context to use a word like 'invented' or 'created'.

As a souvenir, I bought a second-hand book about American history as a souvenir at a local flea market. I bought a second-hand book about American history as a souvenir at a local flea market.

The way you wrote this initially works ok, but it would sound more nautral to put this clauses within the sentence.

I also dived intosampled the local cuisine and, overall, greatly enjoyed my trip. I also sampled the local cuisine and, overall, greatly enjoyed my trip.

'Dived into' is ok, but it sounds a bit unnatural. I'd use a verb like 'sampled', 'tried', or 'experienced' when talking about trying new food. You don't need to add 'overall' but it makes the paragraph stronger by wrapping up the thought.