Completely normal for them to be skittish, it takes time for them to adjust to their new home. Could take days weeks or sometimes even months to come out of their shell. Try feeding every couple days and remove all uneaten food after 20min.
He should eat within a couple weeks tops but probably sooner.
I usually avoid having hiding spots because if there are some all they do is hide.
I prefer open lightly planted tanks with lots of swim space.
Just be patient and I'm sure it will come around soon.
You could also add some fast swimming dithers in like danios, that sometimes help them feel more comfortable, they may get eaten but will make him come out a lil more also.