It is closest to the Swan, so you could go to DD or AK & bus to the resort. You could also bus to the Studios and take the boat to the Swan. My personal choice, if its not too hot, would be to bus to the Studios & use the walkway along the water between MGM & the Epcot resorts. Have a great stay at POR!
There is a pathway behind] the swan that takes you to Fantasia Gardens. We made the mistake once of walking there from the Boardwalk, but we went out the front entrance of the Swan and had a hard time getting over there! Turns out there are signs directing you to the courses that we totally missed!
If you exit the Swan's back entrance, bear left toward the pool, it's not hard to miss (unless you're me and think you know how to get everywhere! LOL)
The walkway is on the other side of the waterway from the boat dock at the Studios. If you follow it all the way to the end the Boardwalk will be on your right & a bridge to the Swan/Dolphin will be on your left. Walk the path past the Swan "quiet pool" & you will get to Fantasia Gardens. Any questions, just ask the friendly Swan CM's!!