Buy shares in a savings plan

Hi everyone, I've been investing in an all word etf for a few years. I've wanted to start with stocks for a long time... Now to the question> I'm at Ing. You can buy savings plans based on stocks there. Can someone tell me whether it makes sense to invest in Apple, for example, for 100 euros a month, or is it worth buying shares as a whole? It would just be a starter. I have a sample portfolio at OnVista, but it's not my money that's there. Greetings submitted by /u/Wonderful