Have you had a bike with brifters before?
I don't know Sora, but in other Shimano gruppi, the front shifter is designed to "trim" the front derailleur with a half-push. It takes a firm push with a long lever travel to shift it. Likewise, the rear shifter can shift one or two cogs at once depending on how far you push the lever.
Cables will stretch on a new bike and need re-adjustment several times in the first few hundred miles.
Honestly, this type of adjustment (including brake pad alignment) is something you should be able to do yourself, because you'll want to make adjustments and replace frequently worn parts without running to the LBS every time. Browse through the Maintenance & Repair section for references to good books (sorry, I don't know any myself). Or if you're already comfortable with hand tools and good shop practices, Shimano's website and the Park Tool website, between them, have everything you need to know.



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Oh, come on, we all call those-things-that-shift-the-chain-onto-another-cog by their French name even though we all know that Tullio Campagnolo invented them...