Hi, Jenny!
Not to worry!
The walk from Epcot to Disney's Hollywood Studios is very easy, although it's easy to miss that first turn once you exit Epcot.
I've included a link here which is actually a map of Disney's Beach Club Villas because this is the closest resort to the
International Gateway entrance to Epcot and the walking path is clearly visible. On this map you'll see the United Kingdom pavilion to the far right and the bridge which crosses over to France just below it. Instead of taking that bridge, continue straight from UK toward Beach Club. (You can see a little cluster of buildings on the map which lead toward a boat dock, with the walkway continuing straight toward Beach Club. HOWEVER, once you exit the park, take that bridge which is the first left toward the BoardWalk. (Turn left before you reach Beach Club.) Next, simply walk along the BoardWalk and turn left at the walkway between Jellyrolls and Atlantic Dance Hall. On the map, note that the walkway continues to the left, then follows the waterway until the last buildings of BoardWalk Resort. You'll see tennis courts (to the left as you walk to HS) and cross under an overpass at which point you'll begin to see the parking lot for Hollywood Studios. That walkway then merges with the walkway leading Guests from the parking area right up to the entrance to Disney's Hollywood Studios.
If you miss that first left before Beach Club Resort, you can simply walk around the lake and head to the same walkway, but this will add 10 minutes to your travel time. (Still, you'll get there.) And of course, if you get tired, you can always take the boat, too (just check the schedule at the dock to see how many stops lie between you and your final destination. There may be one...or several, depending on where you are at the time.)
Send more questions as you plan this great trip, Jenny; we love to help!