The route you’ve put up isn’t particularly easy. It’s got about 700 m climbing in it and some short, quite rough bits, both up and down.
Can I suggest you do a variation on it? Leave Buxton and ride up to the top of Long Hill (A5004) then go left down into the Goyt Valley. You then have a choice
For a shorter route, cross the Errwood dam and turn left up the Goyt Valley, returning to Buxton along the route you found.
For a longer route, turn right shortly before you reach Errwood dam, down a small tarmac track with a vehicle barrier and go down to Fernilee reservoir, then follow the track (flat, old railway line) north to the northern dam and cross there. Follow the tarmac left and climb a tarmac road that goes to the right (don’t take the first path into the wood; it doesn’t go all the way through). At the top of the tarmac road, go left and follow the forest road south. When you pick up the forest road, you are back on the route you have found and can follow it back up the Goyt valley to Buxton.
Either route is easy to pick up on the OS map