This seems like a really vague question to ask considering not much has been said about the story proper. All I can gather is that this is some kind of adventure story.
In that case, I'm going to be broad about this.
This part is somewhat important to their characterization and dynamic in the story outside of a fighting scenario so it'll be awesome to get some input
In which case, consider this. Look at your notes, or whatever plans you have about the next part of the journey, and then see what you can put in this small break that will improve the plot later down the line. Maybe you have a planned boss that the heroes can't defeat, only for them to pull out something they acquired during this small plot line. Or maybe you can look at what you've written so far and see if there are flaws in characters that need to be fixed, maybe explained, or even further push whatever you have in mind. You can also foreshadow, as in have the characters allude to what is to come.
I'm giving these suggestions under the notion that I personally prefer filler episodes to have some meaning later on. Not that I dislike filler as there are times I do enjoy them, such as beach episodes in anime. I figured if you're going to pause the adventure, then just give us a preview of what is to come within the narrative, or add to what has already been established.
If I can give some example, I'd like to use One Piece, the manga version at least (I haven't watched the anime). Possible spoilers if you are reading it.
I currently read the Water 7 story arc, and that whole arc is about Robin leaving the crew, the Straw Hats being framed, Robin being arrested, and the crew bailing her out, and Franky's story being told alongside. But before all that, the beginning chapters in this story arc are just establishing all this. The crew's ship is in dire need of repairs and they all go exploring. Lufy and Nami are exchanging their treasure for currency and looking at a replacement ship, Sanji and Tony are shopping for food, Zolo is buying a new sword. This may not be exactly filler as there are events happening within that will add up later on to the main plot of the arc, but these small things that can be skipped over have been utilized as a set up for things to come.
Maybe you can do something like that. Just write something that appears mundane, but becomes important later on. Something to keep the reader interested in the plot as a whole while still just giving them bits of mundane personality. The everyday things can be used to further the plot and characters, even if it is filler.
I hope all this helps.
