Symbolic Logic
I recommend a rare but lucid book “Symbolic Logic” by Frederic Brenton Fitch.
Although it introduces unconventional logic axioms, this does not obscure the introduction he gives to his semi graphical proof notation which I have found extremely easy to learn and find proofs within.
It is graphical somewhat as the Python language is graphical in its use of indentation.
Fitch’s ideas are akin to those called “natural deduction”.
As a student I proved that with simple and obvious modifications to Fitch’s propositional calculus, his theorems were identical to those of the more conventional predicate logic as given by Quine.