How to figure out if you can upgrade your MacBooks's hard drive
Amazon.com: UGREEN SATA to USB C Adapter Cable for 2.5" SSD and HDD Hard Drive Connector 5Gbps Support SATA III UASP Thunderbolt 3 Compatible with Samsung Seagate WD Hitachi Toshiba MacBook Pro :
Brand Culebacu Apple MacBook Air/PRO/Reting USB 3.0 Hard Drive Case Box Converter, USB Hard Disk Case, USB 3.0 to Mac SSD Case Enclosure A1466 A1465 A1398 A1502 - China Hard Drive Enclusure