I know my son-in-law did not attend driving school in Finland to obtain his license, but he had to receive a certain number of hours of instruction by someone with a valid driver's license. Finland states it this way -
"You must receive a minimum amount of instruction in order to obtain a driving licence. The required amount of instruction depends on the licence category. You can get driving instruction either at a driving school, from a person with a driving instruction permit, or a combination of the two."
My son-in-law was required to take his driving test with a manual transmission or his license would have restrictions that wouldn't allow him to drive his own Fiat Punto with a manual transmission. If I visit my daughter & son-in-law in Finland, my Wisconsin driving license is valid as long as my stay is under one-year.
Taking a driving test with a manual transmission only applies to a CDL (commercial driving license) in the States, & you have to pass three different tests (pre-trip inspection test, backing maneuvers test, and the actual driving test itself) to obtain a CDL. There are numerous written exams, too. Items like air brakes, tanker trucks, hazard wastes, school buses, etc... are all individual written exams you must pass. Someone driving a dump truck may settle on a class B CDL, whereas someone driving an 18-wheeler must have a class A license. Thus, there are different levels of certification.
I won't speak for every state, because this may vary from state to state, but everyone in Wisconsin must pass a written exam to receive their temporary driving permit, which allows you to drive with another licensed adult or driving instructor. Everyone must also pass a Wisconsin DMV driving test.
Only students under the age of 18 are required to take driver's education (30 hours of classroom or inline instruction/12 hours of btw lessons, which include 6 hours of driving with a licensed instructor & 6 hours of observation time (with a driving partner). Instruction can begin at age 15 now. Those under the age 18 must also obtain 50 hours of driving practice, and 10 of those hours need to be night time driving. The actual driving test can't be taken until they turn 16.
The first 5 hours with a driving instructor may be doubled. Thus, I give my driving students 11 hours (5 hours x 2 + 1 hour = 11) credit that can be counted toward their 50 hour practice driving requirement, which means parents or guardians are responsible for the remaining 39 hours of practice/instruction. Classroom & behind-the-wheel lessons have reached approximately $400-500 in my area.
If a 16-18 year wants to get their driving license in Wisconsin, they must complete 30 hours of classroom/online work, pass the written exam, complete 12 hours of btw lessons, 50 total hours of supervising driving practice, & pass the DMV driving test.
An adult (18 & older) doesn't have to jump through all of these hoops, but they still need to pass the written exam & the Wisconsin DMV (Department of Motor Vehicle) driving test. I will have an adult student at times. He or she will just purchase a couple btw lessons to help them pass the DMV driving test. If an adult student doesn't have someone to practice with, they struggle big time. My toughest students have been the adult ones. Most haven't taken the classroom portion of the driver's education. They studied the Motorist Handbook just enough to pass the written exam. Most don't practice much with someone else, & most drive with me alone. They lose the observation time that young drivers are required to have.