[kretaceous]

The downvotes are probably because you said "start with C" while the OP has clearly stated they have experience with C and use it in their day job.

P.S. I haven't downvoted you.

[junon]

Oh I missed that line, thanks. The advice still stands, however - perhaps not to OP. But I think it's even more reason to learn C++20 in OP's case.