If you just want to learn it to read it, there's no better combination than Wheelock's Latin and Hans Orberg's Lingua Latina Per Se Illustrata. Wheelock gives you the grammar, and reading Orberg will improve your reading speed and comprehension by leaps and bounds.
To learn Latin, I always suggest Wheelock--I think the fourth edition was new when I studied Latin, so I can't swear by the 7th edition, but it probably hasn't changed too much. Others frequently advocate for LLPSI because it's closer to immersion (the way most modern languages are taught) than grammar-first (Wheelock's and my preferred method). Obviously you'd need more than just the first volume of LLPSI, but that's where you'd start.
As for Latin resources, the Latin Library has a ton of free texts, including the Latin Fathers. At least some of them are OCR scans, though, so be aware that there may be typos here and there.
For Ancient Greek... I learned with Groton, which tries to be the Wheelock of Greek, but doesn't do as well. Every time someone asks this on r/AncientGreek, there's never a consensus on the best textbook.
Once you understand how the language works, you can start reading texts without translation, as long as you have a dictionary handy. My recommendation is that you always try to figure out each word yourself before turning to other resources, but if you get really stuck, you can use parsers (Whitaker's Words for just Latin, Perseus has parsers for both). Perseus also has a lot of texts available, both original language and public domain translations, and the code for their database is open-source. Even if you don't use their parsers, Perseus has Liddell & Scott (the Liddell-Scott-Jones "Great Scott"/"LSJ" and the "Middle Liddell" sizes), Slater, and Autenrieth dictionaries for Greek and the Lewis & Short (as well as its abbreviated Elementary Lewis) dictionary for Latin.
If you're flush with cash, the Loeb Classical Library has, I would like to say, almost everything in Greek and Latin side-by-side with translations. It's an easy way to read and study the classics without first learning the languages (or while you learn the languages). If you have access to an academic library, you can usually find/access them without having to buy them. Now that I work far from academia, I just have to lament sadly that I can't afford it. (Before I get too old, maybe I'll buy an individual license for the digital version.)
As for Church Fathers in general, like I mentioned above, many Latin Fathers are available for free, and most (not quite all, I don't think) Church Fathers are available for free in translation. The Greek texts are harder to come by, mostly because they aren't collected in one quick place that I'm aware of (except perhaps sites like Perseus).
Trying to find free resources can be a challenge because university presses are behind most publications of classical texts, which means (1) they get to copyright the texts because of their translation, critical apparatus, or editing, and (2) those copyrights last a long time when assigned to an institution instead of a person, especially when they keep refreshing them with new "editions" that barely change.
That said, it can be difficult at times, especially around Chapter 16. I would recommend picking up a copy of Wheelock's* as well, which is much more focused on grammar and structure. You might want to either go through Wheelock's and LL together, or tackle Wheelock's first and then LL second.
If you get stuck on something, swing by the Latin StackExchange (https://latin.stackexchange.com/).