Planning back-end web development

I am starting backend as I have finished the front end user interace. Is there any planning paradigms for backend that I can follow? Like modelling database first and then handling users for registration? Any planning resource out there?

I tried searching, but all I find are tutorials, I am searching for a guideline to tackle backend development step by step. If it helps I am using Laravel PHP as the backend framework. I also want to consider security as one of the pillars, where in the timeline should I implement security algorithms? Any experienced backend developers, please help me out.