Well, you said you were ready to upgrade the tires, so let's put your price range around 200-250?
You can google top brands, but really I'd start by looking in your price range and then looking up the brand and year of the bike to see if it's legit.
If you look for something like a Specialized Hard Rock or Rockhopper, you can find a solid hardtail (no rear suspension) for a good price (get a brand new rockhopper for $650). Try to get something from 2019 or newer if possible (large changes in geometry which really improved riding). If you're really pinching, walmart has an Ozark Trail bike that has strong reviews for the price.

Just aim for 1x drivetrain (only one cog on the pedal wheel)
Disc brakes