The Molecular Biology of the Cell is the standard text. https://www.amazon.com/Molecular-Biology-Sixth-Bruce-Alberts...

But you'll probably benefit from taking an Edx course https://www.edx.org/course/introduction-to-biology-the-secre...

Molecular Biology of the Cell is a wonderful book (my first PhD advisor was one of the authors of the 3rd edition), but if you're more interested in the purely genetics side of things then I'd recommend Genes by Lewin - it's definitely the book I relied on most during my undergrad degree, and it's written in a way that largely lets you bootstrap from not having a strong biology background.

Others recommend MBoC, I personally liked Lodish better. More importantly, cell biology is one of those subjects that can actually be fairly light reading. It doesn't burden itself too much with arbitrarily named cytokines, or the astonishingly complicated biochemical pathways and enzyme names. The processes that govern each aspect of the cell are surprisingly very unique so each chapter is a veritable cornucopia of amazing methods our cells use to solve their problems.

The pretty pictures don't hurt either!