Saint John NB walking question----

[Jetswdo]

 We have been to Saint John on a prior cruise and have done the main tourist things on a shore excursion.  For our upcoming cruise, we would like to just walk around and have lunch, probably at Billy's or Steamers.  We would like to go as far as the Jewish history museum---  ( also bought tickets from cruise line for HOHO bus, fortunately our cruise ship is the only one scheduled in town that day)  If we just walk all the way to museum area, what are the easiest streets (least hilly) for us to use.  We are in late 60's early 70's,  I know it is about a 15 minute walk or so from the ship--- I just don't want to be out of breath when I get there!  Also, if we walk back to the ship by way of Billys area,  I think that way is down hill?  What I am babbling on about, is that if the line is ridiculous to get on the bus (museum is stop 5), then we would rather just walk it.  ( I can pick up the bus at another stop just to do the 1 1/2 hour loop around)   Just want to keep our options flexible.