99 Dakota intake gasket

I have a 99 dakota 318. Ive noticed a significant loss of power, have a small ding when I get on the gas and I go through alot of oil. Also sometimes its hard to get it to idle when I first start it up until it gets warmed up. Also the check engine light comes on every few weeks for a day or two then goes off. I was told that my intake gasket of blown and was estimated around 400-500 dollars to get it fixed. Its out of warranty with 123k miles on it. Just wanted to know if thats what is wrong with it before I fix it and just how much power will be brought back. Also if it can be done myself or if it will need to be tuned up or anything afterwards. Any help would be great, thanks.