Migrate database to Azure I have a 600GB database that I must transfer from an on-premises machine to an on Azure VM machine (IaaS)
I would like to use the dbatools copy-database tool for this
for this I will have to know what will be the best storage method that allows me to have a fast transfer

local backup then restore on the Azure machine
remote backups directly on the machine in azure
a backup and a restore from storage azure blob
In my experience, the fastest way to get this done is to copy the backup up to Azure blob storage, then restore from there. The fastest way to do that move in the testing I've done is through the use of AZCopy. Copy to the drive that's already mapped to your VM and there's nothing you have to do special to then run the restore. At that point, it's just SQL Server doing it's thing.