Straightening hair at home: yes or not?

Hi! I have wavy long black hair, I can get them almost straight after I use hair straightener but it lasts like couple hours.

I want totally straight, heavy dropping, hair. Is it possible to reach that goal at home as I can if I have, let's say, keratin treatment by professional hairdresser?

What treatment use? Which products? Take note I am located in EU.

Thank you!