M.2 SSD have two flavors:
SATA: You can use an adapter to a normal sata connector, then use a USB adapter. https://www.amazon.com/StarTech-2-5in-Adapter-Converter-SAT32M225/dp/B00ITJ7U20
PCI-E: You cannot use an adapter to SATA. You would have to get a PCI-E M.2 adapter you can install in a computer. https://www.amazon.com/StarTech-com-M-2-Adapter-Profile-Express/dp/B01FU9JS94
2.5" SATA SSD, USB no issue.
mSATA SSD. You need a mSATA to SATA adapter. https://www.amazon.com/Syba-mSATA-2-5-Inch-Adapter-SY-ADA40050/dp/B007PPZ2I8
M.2 SSD have two flavors:
SATA: You can use an adapter to a normal sata connector, then use a USB adapter. https://www.amazon.com/StarTech-2-5in-Adapter-Converter-SAT32M225/dp/B00ITJ7U20
PCI-E: You cannot use an adapter to SATA. You would have to get a PCI-E M.2 adapter you can install in a computer. https://www.amazon.com/StarTech-com-M-2-Adapter-Profile-Express/dp/B01FU9JS94
2.5" SATA SSD, USB no issue.
mSATA SSD. You need a mSATA to SATA adapter. https://www.amazon.com/Syba-mSATA-2-5-Inch-Adapter-SY-ADA40050/dp/B007PPZ2I8
Does this laptop have a 2.5" sata bay? If so I would take the existing ssd and put it in the 2.5" bay using an adapter like this and then use the m.2 ssd slot for the egpu because the m.2 ssd slot will have better performance and avoid potential bios whitelist issues
M.2 SSD have two flavors:
SATA: You can use an adapter to a normal sata connector, then use a USB adapter. https://www.amazon.com/StarTech-2-5in-Adapter-Converter-SAT32M225/dp/B00ITJ7U20
PCI-E: You cannot use an adapter to SATA. You would have to get a PCI-E M.2 adapter you can install in a computer. https://www.amazon.com/StarTech-com-M-2-Adapter-Profile-Express/dp/B01FU9JS94
2.5" SATA SSD, USB no issue.
mSATA SSD. You need a mSATA to SATA adapter. https://www.amazon.com/Syba-mSATA-2-5-Inch-Adapter-SY-ADA40050/dp/B007PPZ2I8