Before you purchase a oscilloscope, Try watching a few of these videos.
Search his website And YouTube channel, for other videos that you might want to watch. He is an electronics engineer, and seems to be very knowledgeable. he is a good source of information.
My advice is don't jump into the deep end, until you learn how to swim. Figure out what you are going to do first, Before you make any major purchases. Learn what you need, and how it is used. The Internet is a great place to start. And you can go broke buying things that you may never need or use.