There is an M.2 slot (unless you have a Celeron or Pentium budget CPU). This is what it looks like with rear cover removed (see p. 45).
M.2 slot circled in red
The slot supports ONLY SATA M.2 not NVME. There is also a part you can get that would allow a SATA M.2 to be placed in the 2.5 inch bay instead of the hard drive. Makes little sense to do that, however. Do open the laptop before you buy any SSD as this slot is sometimes not present where the Manual suggests it should be.
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