Starting off with a syringe is perfectly fine. There are plenty of reputable suppliers that wont result in contam. I dont recommend agar straight away because it requires a lot of time and monetary investment.
Unnecessary.
Feel free to check out my grow thread I went through the exact same learning experience. Its important not to try too much at once and overwhelm yourself and cause issues when there doesn’t need to be any. No one (or atleast most people) dont go straight into cloning/cuttings before they’ve harvested their first bud or bred their own seeds