Fungus, yes
And the affected leaves are dead or dying, yes. (oh, I've read it somewhere already
You can try to save part of the leaf still green, if there's a part large enough without fungus spots. Cut large! All the dark spots with yellow around are fungus. The necrotic zone is spreading spores.
The yellow leaf is just spreading spores… You shouldn't let be a leaf dead and contaminating the area.
And treat ! Systemic fungicide is you friend.
Now make a review of the conditions you give it, sun, air, water, something must be wrong. (I have the same issues with Gongora…)