I have a Lonovo ThinkPad that only had a small hard drive but has a micro SD card connector. 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.
Titan Gray Samsung BAR Plus 256GB USB 3.1 Flash Drive (MUF-256BE4/AM) with Up to 400MB/s Transfer Speed
69 Review
Kingston DataTraveler SE9 32GB USB 2.0 Flash Drive for Reliable Data Storage (DTSE9H/32GBZ)
69 Review
32GB SanDisk USB Flash Drive (SDCZ430-032G-A46)
78 Review
Compact and Convenient: SanDisk Cruzer Fit USB 32GB Flash Drive (SDCZ33-032G-A11)
66 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
8TB Seagate Backup Plus Hub Desktop Hard Drive with Data Recovery Services
56 Review
Shock-Resistant Transcend StoreJet 25M3 USB 3.1 Slim Portable Hard Drive with 500GB Capacity
99 Review