If you're on windows, right click the start button in the lower left corner and click "Disk Management"
Find the desired drive in the list, delete all partitions and create 1 new Fat32 partition.
Don't mess with Drive 0 unless you know what you're doing. (It's the C: drive windows is installed on.)
On macOS or Linux you'll need to find it. Pretty much just search "Disk" in whatever your computer uses to search.
An easy way to find out what drive is your drive is to simply see the sizes of all the partitions. Your main HDD/SSD will (Most likely anyway) be much larger than the flash drive, while having 2-3 partitions. (Storage, System Reserved, and Recovery) Your flash drive will be a single-partitioned 64GB drive. (Also under the Disk # it will say "Removable" and not "Basic")
On macOS/Linux you can actually make the drive appear as 2-4 drives (Pretty useless but I thought I'd throw it in)
*This actually crashes windows
*