The best time for fishing is whenever and wherever you can get out to wet a line.
Some days, fish will mostly actively feed during dusk or dawn, but some days, fish will feed all day.
For shorefishing anglers, they are more restricted since fish are most likely to visit shallows during dawn and dusk. When the sun gets higher, fish may retreat to deeper areas of the lake that are out of casting range for most anglers.
During midday, look for fish in areas of cover where they can seek shelter from the sun. Thicker weed beds, under trees, deeper areas of the lake...fish will be there...and if you do everything just right, they may very well go for a little midday snack. However, you may need a watercraft to reach these fish. You don't necessarily need a boat for smaller lakes. A friend of mine used to fished out of a beach toy...and even a canoe mold. He's a bit strange in the head though LOL.
So just get out and fish and not worry too much about when you should fish. Put in the time to learn about your fishing location, observe how the fish behaves, and you'll be doing well soon.