Ask the mechanic about the specifics of the bearings. They'll know whether the hubs, cranks, etc., need special attention, perhaps a different grease, or are fine as-is with only the usual seasonal maintenance.

Other than that, ditto what everyone said.

The last time I cycled routinely in rain was 30 years ago with a cromoly frame bike. As it turned out the frame was remarkably rust resistant, despite the nicks in the paint, and needed only occasional attention. I cleaned and lubed the chain and gears often. But after trying various lubes I settled on Phil's green grease for the hubs, crank and headset. That stuff was waxy without being sticky, tenacious, and water resistant. Never had another problem with all weather riding after switching to Phil grease. But that was decades ago. No idea whether it's still considered the best.

Nowadays with an aluminum frame bike I'm mostly concerned about the simple Suntour spring suspension forks. I don't know how effective the seals are, whether they're considered only dust seals, and whether they're still good after seven years. So I'll probably disassemble it after a couple of wet weather rides to see how it's doing inside. But I don't expect to ride in the rain if I can avoid it.