Where to start with DSP?
so I am wondering where can I go to form an understanding of DSP from the ground up.

There is a great list of resources in this answer What Resources Are Recommended for an Introduction to Signal Processing (DSP)?  You should spend half an hour with each one and then decide which fits your own learning style the best.

My skills in calculus are also quite bad.

That's a problem. DSP is by nature fairly math heavy and if you lacking some fundamental skills, you will we miserable the entire time. It's like trying to build a house but all you have is a hacksaw and a bent hammer. Get the right tools first. At the very least make sure you are familiar with complex number and the associated math. There are plenty of resources to do that, including Khan Academy.