Post covid many bike companies were in big financial trouble so new bikes cost less than used, but that's mostly resolved or the companies are just plain failing, so definitely look for a newish (aka few years old) used bike and you'll get a lot more for your money. Manufacturers are all pushing ebikes (with electric motorcycle specs) these days and now 32" wheels (don't get me started - and I'm 6'5") so depending on your planned riding and budget 29" HT or full-suspension mountain bike (off-road, trails, casual), or hybrid style / gravel (light off-road, commuting, touring). Focus on a known brand, quality basics (in the order of (frame, fork, wheels, drivetrain, brakes) and figure it out from there. Avoid cheap versions of ebikes, full suspension or carbon; there's typically good reasons for the price and usually you can't fix or upgrade them - although the Walmart Ozark Trail is a decent attempt (but still has major short-comings; you're better with something like a Polygon HT).

Nope the original poster, but check out gravel bikes. They’re essentially the geometry of a relaxed road bikes with massive tire clearance to make the rides more comfortable.

Lots of new bike tech, so depending on how old your “old” bike is. I would recommend going to stores and doing some test rides. Enjoy!

Simple Batavus analog bike. Don’t know the type. It’s an eleven speed and has disc brakes front and back that make a horrible noise when you come to a stop. Back one makes noisy because the bike leaks oil on the disc. No idea why the front one is noisy. A project for one day.

Enviolo stepless bicycle automatic transmission (never manually shift again, accelerate while continuously shifting under load), with a carbon fiber belt drive (maintainance free, silent, never get grease on your pants or hands again), and Bosch Performance Line mid-motor (strong zippy performance from the geniuses who paid a €90 million fine for Dieselgate), plus GPS tracker with "recovery service" (required for insurance).

https://enviolo.com/

https://www.youtube.com/watch?v=TQrgKBQrkag

https://www.youtube.com/watch?v=6xY2S-9gjHI

https://www.koga.com/en/enviolo-gear-hub

https://www.koga.com/en/bikes/e-bikes/evia-pro-automatic?fra...

It's a dream bike, optimized for comfort and city riding, but Koga is not available in the US, though.

Here's an American bike that has similar features (not as nice as the high-end Koga Evia Pro Automatic though), the Harley Davidson Rush/CTY (step through model is easiest to mount/unmount/ride):

https://www.youtube.com/watch?v=4SjN8RN9g7Y

https://www.youtube.com/watch?v=KoX9S5UhETE

https://serial1.nl/

The Enviolo Automatic also come in a heavy duty version paired with high performance motors for bakfiets (cargo bikes), for 3-4 children, big dogs, and groceries:

https://batavus.com/en-nl/products/fier-3-bbfn3

https://www.dw.com/en/bosch-pays-90-million-euro-fine-over-d...

https://en.wikipedia.org/wiki/Volkswagen_emissions_scandal

Edit:

Fair, they're ideal for city bikes, stop-and-go traffic, and the flat Dutch landscape where they're produced, where the biggest "mountains" you encounter are the bridges over canals. Their city model has 310%, trekking 380%, and the new utility hub has 400% gear range, which you can use on a normal bike, bakfiets, or speed pedelec.

https://enviolo.com/news/enviolo-launches-the-utility-hub/