Boekhouder gezocht voor particuliere aangifte

Toelichting op de werkzaamheden:
I would like some help with my tax return coming year as I got a lot of extra money this year as severance payment from a previous job. I am not sure where and how to declare this and if there is a way to not get taxed too much for it.
I am working for a new employer since December 1st. I own two houses in Holland, for only one I am still paying mortgage, the other one is paid of.
I don't have a registered partner and no children.

Thanks in advance.

Deadline: asap