[chmurf]

when you book flights, you'll be offered different fares.
some (usually called "light" or "basic economy" by some airlines) will not include checked luggage. So you need to double check what fare class (rate) you book

advance seat reservation may come for a fee

on main airlines you do get meals and drinks, included (only some airlines, classed as low cost, like icelandair, will not include meals in their base rates, but there again, you're offered to purchase a rate including those things, just make sure you understand what you agree to pay for, it's stated what's included, clearly when you book)

please note that covid protection related measures will have some airlines not offer drinks or meals.