All of the complications and complexity in QM/QFT are from doing calculations that map to the extremely coarse-grained boring low-energy reality we spend all of our lives in. If you ignore that, the underlying math is exceedingly trivially formulated. It's like 2 powerpoint slides to show what CUDA arrays and ops are needed to underpin a quantum field theoretic calculation of quarks and gluons inside a proton for example.

Unfortunately you're probably not going to be satisfied with that, at some point you need to connect these simulations to real measurable parameters and this is exceedingly non-trivial :/

Starting from the other end, pure old-school undergrad quantum mechanics is really the easiest way to connect to measurable quantities and this is why it's used in all of engineering, quantum optics etc. It just provides the right amount of detail.