Turkey poults are less survival orientated than young chickens. They don't have the same roosting or sheltering instincts so will get soaked if it rains and need rounding up every eveing to get them into a house.
Ideally, use proper turkey rearing food, but I have used normal chick crumbs in a pinch (few places stock turkey poult crumbs here), followed by mixed corn with added veg oil in the last few weeks when I wanted to fatten them. They may need a little watching to ensure they've got the hang of where the food is to start. Tapping it with a finger, like a break of a bird often helps. They make a lot of mess... They love grass and free ranging turkeys have a far better flavour because of it.
I've had turkeys and chickens together and never had a problem with blackhead which is generally thought to be a problem: I believe this is only a problem in confined or intestive situations.
Mine were under heat to 4 weeks, with the final week being nights only and then shut in at night in a warm shed for another couple. To start, have them in a pen with heat near one end so they can choose how warm they want to be. If they're all at the far end away from the heat, raise the lamp so the heat is less intense, lower, or put in a stronger bulb if they're all huddled under it. Mine were confined to a pen when first out so they didn't get themselves lost, until about 8 weeks old, possibly a little more.
Make sure your perches are good and strong and not too high because they get very big and heavy! Having said that, mine often roosted on the apex roof of my garden shed. Probably part of the reason it's now just a pile of firewood.
Turkeys are lovely: they are very curious and they'll come up and peck at interesting things like zips and fingers (ow) to find out what they are and they love red things. It is very hard not to become attached. Enjoy!