4 years to get there? Hmm i dunno.
You need 2000 hours 500 multi and your ATPL subjects.
It will take you a couple of years from now to get to 1000 hours before you get a look in on a twin. Then you need to get 500 multi and do your ATPL.
Add another year or two to that if you become an instructor as you will need to be a grade 1 with META.