First time chinchilla owner...feeding guide

Hi,

I'm getting a chinchilla (hopefully real soon). I'm waiting for the breeder to text me for pick up once he/she is weaned, so when s/he is 8-10 weeks old (maybe wee older). I was hoping if you lovely expert folks could help a newbie out with feeding questions. I've done some research (still researching), these little cuties are have a very delicate digestive system, so I don't plan on feeding mine foods with high sugar intake. However, I read that dried rosehips are considered a daily safe treat (max. 3 per day), they're rich in vitamin C & fiber and dried chamomile flowers are safe too, they make them relaxed and de-stressed. Does the rosehip has to be whole? or cut (powder-like) should be fine too?

I also have Alfalfa and Western Timothy hay on the way. I'm a suppose to feed the little one Alfalfa hay daily then switch to Timothy at a specific age? Also, can I mix a little bit of both hay, maybe more of Alfalfa since it's beneficial to kit.

I appreciate you answering my questions. Just want to provide a suitable care for my new pet, given I haven't owned one before :-)

Thanks,
Heath