^Pretty much this.
To get strong, follow one of the many Powerlifting templates that can be found here on TN. I am not a powerlifter myself, but have heard good things about 5/3/1. And as Mr. Wendler has a subforum here, you can't beat it for convenience when questions arise.
To lose 20# of fat, you have to average a fairly significant caloric deficit for a fairly significant amount of time, all the while maintaining a vigorous weightlifting routine. And just as there are a number of proven powerlifting programs out there, so too are there myriad proven approaches to achieving a sustained caloric deficit. In that regard, my personal favorite is carb cycling; if you search TN, you'll find several articles and a number of threads about it.
So in a nutshell:
1) Find a powerlifting program that appeals to you.
2) Find a diet you can live with.
3) Commence grinding.
Best of luck, and keep us posted re your progress.