I have a Lonovo ThinkPad that only has a small hard drive but has a micro SD card port. I have a 256GB microcard in the slot so I can backup everything to a 256GB USB flash drive. It takes a while, but having a backup about once a month gives me peace of mind. I use smaller flash drives more often to back up work done between full backups.
Kingston DataTraveler SE9 32GB USB 2.0 Flash Drive for Reliable Data Storage (DTSE9H/32GBZ)
69 Review
Sandisk Ultra Flair 128 GB Silver USB Flash Drive: Reliable and High-Speed Storage
65 Review
Compact and Convenient: SanDisk Cruzer Fit USB 32GB Flash Drive (SDCZ33-032G-A11)
66 Review
Samsung BAR Plus 128GB - High-Speed USB 3.1 Flash Drive Titan Gray (MUF-128BE4/AM)
67 Review
2 TB External HDD ADATA DashDrive Durable HD650, USB 3.2 Gen 1, Blue
55 Review
18 TB External HDD Western Digital WD Elements Desktop, USB 3.0, black
95 Review
π Seagate Expansion 3TB Portable USB 3.0 External Hard Drive (STEA3000400) in Black
60 Review
2 TB External HDD Western Digital WD Elements Portable (WDBU), USB 3.0, black
84 Review