The differences between motels and hotels are chiefly that motels have exterior corridors whereas hotels have some or all interior (AKA hallways); and that motels allow guests to park near the room—sometimes right outside. Motels also tend to be low-rise--a maximum of three stories--and offer minimal amenities. Hotels will often have a restaurant, bar, business center, fitness center, and pool/hot tub. Motels usually don’t offer these things, though many offer limited breakfast in a space adjacent to the checki area. Motels in hot climates will often have an outdoor swimming pool.
Also worth noting, motels typically do not have more luxurious room categories above the standard run-of-house. Hotels often do.