How to change shipping prices?


Im trying to figure out how to change shipping prices. I want all my items to charge $2.99 for shipping and offer free shipping when $25 is spent (think I have this promo already working). Right now my shipping is all jacked up. Some items are $2.99 and others are $3.99. Ugh! Also, I dont have shipping charges within each individual item set up. Im sure there is a blanket way of doing it, just cannot figure it out.

Thank you!