Look up the exact model number and find the service manual

Yes, you can figure out if the RAM is soldered or replaceable without opening the laptop — but you need the service manual, not the marketing spec sheet.

Manufacturer spec pages often use vague language like “memory: 8GB LPDDR5.” That “L” in LPDDR means soldered. But sometimes they just say “DDR4” and it’s a slot. The only way to be sure is