Hello Kam and welcome to the forum
Ghosts are a great hardy species well suited for beginners, so you shouldn't run into any issues, but if you do just search the forum and/or ask. I've raised many myself and my longest lived mantid was a Ghost female that lived 15 months.
Regarding the raspberries it should be a non-issue as it is highly recommended to wash your hands before and after handling any pet to prevent issues of passing any materials. In nature though some species may get a taste of raspberries once and awhile from some of their prey, or passing through a area with them.
Mantids are good at regulating what is good or not for them thankfully, and will not eat or throw-up things they should not have. I've heard of some using bananas occasionally too, but all fruit is a weekly treat at most and best avoided.
Mantids though love honey and is a great treat that most keepers have used for years - just dip a toothpick into it and offer it to them (some need a taste first, so placing a small amount on a forearm lets them try it when they clean it off (they are like cats in cleaning)). In nature they have access to honey/pollen from bees and other flying prey.
Just be sure to get real honey from a bee-keeper, farmers market, or such as the stuff sold in stores labelled 100% honey isn't even considered honey by most people even in the food industry (due to the excess filtering and unclaimed additives) - see here...
