I ordered a sheitel and two aprons on line before yom Tov. They were delivered on chol hamoed.
1. Can I wear them
2. If not can I try them on?
It is permitted to wear the clothes on Chol Hamoed since you bought them before Yom Tov, the fact that it arrived on Chol Hamoed is not an issue at all. We are even allowed to buy clothing during Chol Hamoed if it is for Chol Hamoed or Yom Tov use. The only issue might be, if you ordered it express delivery in a way that the gentile could only get it to you by working on Yom Tov itself. Then you would have to wait a day after receiving it to put it on, so you don’t benefit from the work of a gentile on Yom Tov.