If you were raising a laying flock you would have certain preferred options. If you were raising them for meat only you would have certain preferred options. Those options do overlap.
I don't know what marketing names are available to you. As mentioned above Flock Raiser is a good choice. In some placed All-Flock may be available. You can typically use Chick Starter but I'd avoid medicated, you don't need the medicine for your adults. What you are looking for is an analysis that gives you a high protein content and a low calcium content. An 18% protein content would work but most people prefer 20%. If you feed many low protein treats or let them forage 20% is probably better because they probably aren't getting that high of a protein content with the overall average. Many people prefer 20% anyway.
All chickens need some calcium, that's why practically all chicken feeds have a minimum of around 1%. Laying pullets and hens need more for the egg shells. If all they eat is Layer, then they should have around 4% calcium, but that much calcium can potentially harm chickens that don't need that much. The easy solution to that is to provide a calcium supplement on the side. I like oyster shell. It is pretty inexpensive and never goes bad. Most chickens are really good at eating what calcium they need, whether that is laying chickens that need more for the egg shells or the ones that may not get enough calcium if they forage or get too many low calcium treats.
Regardless of the name, I'd suggest you look for a feed with 20% protein and around 1% calcium and offer oyster shell on the side.
If yours have access to the ground and your dirt has bits of rock the size of a green pea or smaller they can find their own grit. You will often see them scratching and pecking at dirt, grit is one thing they are looking for. I've never purchased grit, had no need. But some people keep their chickens in a way that they don't have access to find their own. If the chickens eat anything that needs to be ground up they need grit (insoluble grit for out British friends) in their gizzard so they can grind it. It doesn't hurt to offer grit on the side even if they can find their own, just don't get concerned if they don't eat it.