Congratulations on getting your sister into treatment - many of us here have been through the same process. Its hard, but not helping a family member and seeing them decompensate is unbearable.
There are some really good new early psychosis treatment centers around the world and since your sister is just starting to get treatment she’d be a good candidate for them. The are usually of very high quality and frequently free (since they are associated with research/universities). Check them out here: