Can I take my old iMac into the store and have them transfer and set up

You need to contact your local store and ask. However migration is incredibly simple. Please read Setup Assistant and Migration Assistant - Apple Community, extremely easy, reliable and quick not to mention much easier than lugging your old Mac into a store.

I live in Austin, Tx and when I purchased my 2019 21.5" iMac, the Apple store transferred my data from my 2009 24" iMac for free. I brought it in and they did it the next day. I know the SA and migration programs are great, but it just gave me peace of mind knowing I wouldn't by a careless mistake screw something up. The sales person said they used to charge $100 but now it's free.