That's disappointing to hear. The 620 should be able to handle those kind of games. Civ 5 for instance is just not that intensive.
Is there a chance this is an issue with DirectX? The crashing would make me think this is much more likely to be a software issue than a hardware one. I've seen people talking about this issue a lot with Civ 5.
Fix for Civilization V Windows 10 crash after launch - YouTube
Maybe it's a driver issue? I'd recommend downloading the 620 driver directly from Intel's site.
Downloads for IntelĀ® HD Graphics 620
I'd also recommend a clean install of Windows to get rid o Dell's bloatware if you haven't already. Might not solve the crashing issue but should help with performance ones.
From the looks of what you bought, you got a really good deal and that looks like a solid computer. I think it has to be more of a software issue.