Pascal is not a low level language - quite the opposite. That being said, various implementations provide low level facilities, including turbo pascal back in the days , and free pascal which I did use in the early 2000s. If I were you, if you like fpc, I’d actually look into Ada ( the OO part is a bit odd granted but works ). You’ll get extremely high control over low level stuff ( it’s used in the embedded world )…
In what way is the OO part a bit odd?
While it may look reasonably clean in the link below, I’ve always found it integrates badly with an existing codebase, the primary problem being that the ‘boundaries’ of the objects are not clearly visible.
https://learn.adacore.com/courses/Ada_For_The_CPP_Java_Devel...
I will add that the existing non oo features are excellent and I would even argue that in many cases you don’t need OO.