You're looking at two separate issues for Farsi - the alphabet issue and the resources issue.
For the alphabet issue, you'll want to make a simple spelling trainer and perhaps some minimal pairs, using these flashcards:
Ear Training: Minimal Pair cards
Eye Training: Spelling and Sound cards
You could get the information you need for these cards from a textbook, but again, given that resources are unlikely to be super for this language, I'd highly recommend taking the approach I did for Japanese - https://fluent-forever.com/hacking-fluent-forever/ - source all that information from a tutor. At the start, have them teach you the alphabet, have them write out all the information you need, come up with example words, coach your pronunciation, etc. (Also in coaching your pronunciation, you can immediately make minimal pairs that are simply good vs. bad.)
I.E., have your tutor say a word, then you say it, then if it's not good, have your tutor mimic what you're doing. Then take the recordings there and do minimal pairs, forcing yourself to figure out whether this was your tutor saying it correctly, or incorrectly. Poof, custom minimal pairs.
Then take the 625 word list in English and have them translate it, then help you create sentences for each word. By the time you hit the end of the list, you'll hit an intermediate level of Farsi, and then you can keep going from there to more complex resources like frequency lists or just continued conversations with your tutor.