Yes, you can take the bus from DAK to FtW, and then the internal bus to HDDR. The park buses drop you off at the Outpost; from there you can take any internal bus to the Settlement, which is where Pioneer Hall, the home of HDDR, is located. The park buses & the internal buses stop at the same platform at the Outpost; you just get off one and wait for the other.
Currently, DAK buses to FtW stop at Wilderness Lodge first. You can also get off there, and transfer to the bus from WL to FtW, which goes directly to the Settlement. The buses from WL run slightly less frequently, but it's still usually faster because there's much less total distance traveled. (It's possible that direct service to FtW without the stop at WL may resume after the current load zone construction at DAK is completed.)
Taking the bus to CR and then the boat to FtW is also a perfectly fine option. The boat dock at CR is behind the main building, near the pools. So you simply walk into the lobby from the bus stop and walk out the back doors to the boat dock. At FtW, the boat docks at the Settlement, a short walk away from Pioneer Hall.
As with any Disney Transport involving a transfer, you should plan on 90 minutes travel time, especially when you absolutely don't want to be late. It's more likely to take about an hour, but the extra time allows for encountering a full bus or boat, equipment problems, or other delays.