Html is dovetailed with CSS and PHP I need an explanation why ?

Question

there is a flow of content cutting across these courses. I see it is more rewarding to enroll in the courses, simultaneously.

Answer 1

That's up to however you learn best. Personally, I enjoy doing multiple courses at the same time and learning more than one thing together, but that doesn't work out for everyone.

But yes, you're right, many of those courses are related to one another; at least with the web technologies. HTML/CSS/JavaScript/SQL/PHP/jQuery all go hand-in-hand with one another. Worth learning them all.