Aurora, as usual, I commend you on taking initiative and looking to learn about and progress to taking on the acts that are most identified with religious Judaism. Keeping kosher is not simple, but obviously the first step is to buy kosher products, as you have obviously realized.
There are on line sites now for many certifying agencies, such as star K. You can google kosher symbols and come up with an array of them. Once you become familiar with how the symbols appear and finding them on products, you will be able to familiarize yourself with which brands of products are already certified kosher. You probably eat a lot of these things (not just Manishewitz products) without even realizing it.
Like others have said, you will hopefully be able to get chicken in a store not far from where you are located in PA. A more extensive list of meat products might require a trip to Philadelphia. You could think of it as making a kosher trip and go in on a free day (or half day-depending on travel time) and, once you have determined where a kosher store is located, you can go in and stock up on whatever meat products you would want to eat for the foreseeable time until you could return. Store it in the freezer and you’ll be all set.
As far as dairy, now that’s a whole other kettle of fish. As you have seen from the DD thread – there are 2 types of milk – cholov (milk) Yisroel, which is milk that has been supervised by a Jew from the time of milking (he does not have to actually milk the cow, just watch the farmer milk it) until it is processed. We are fortunate that in our times we have a large variety of dairy products available that are cholov Yisroel.
As zahavasdad said, from where you are coming, there is no requirement for you to restrict yourself to cholov Yisroel products. Rabbi Moshe Feinstein, of blessed memory, was a great authority in Jewish law in the last 50 or so years in America. After examining the issue, he declared that because farmers would be afraid to mix anything into their cow milk products (pig or camel or horse milk for example) because the USDA would give them a fine, so we can rely on the fact that these products only contain cow’s milk and we can drink almost any milk product that is sold in regular grocery stores (I’m not sure about thinks like raw milk or products that have added vitamins or minerals). Other dairy products, such as cheese, do have other ingredients, like rennet, that require kosher supervision, so be sure to check for the certifying symbols on your products.
The only suggestion I have in addition to the above would be to avoid eating meat and milk together. This may sound simpler than it actually is since many products do have some dairy products in them that you would not suspect. That includes even things like cookies (Oreos have an OU-D certificate).
Once you feel comfortable with this, you will decide what new aspects of kashrus you want to look into.
As always, Hatzlacha!