Yes, it is possible.
Why don't you post your deeper questions here just as you did now?
Reddit is also a fantastic place filled with even more intelligentsia and you can get answers very quickly.
To answer your other doubts:
If you have an interest in learning the Path and can generate detachment, then you will easily adopt into this simple but important school.
The most important process in Theravada is going through the Stages of Insight (see "Mastering the Core Teachings of the Buddha).
This Stages of Insight process happens automatically when practicing awareness meditation (vipassana) correctly.
One must retreat: make an extensive amount of time to practice and pay clear attention to mind (strong Five Faculties on the Four Foundations) all day and night, with moderate sleep and food.
Even though most of us are not actually Enlightened, walking the path to it is just as simple as this. Being clearly, effortlessly aware of present reality. (read: high level of 5 Spiritual Faculties)
The "advanced questions" are all about Right View and understanding the component structures better and learning to let go of attachments (this might involve reading non-Buddhist things).
Although I do not recommend it for beginners, the retreat can be done without any retreat instructor. One may use a retreat manual.
In many cases, a retreat manual is better than a bad retreat place where people just talk all day and share their problems/life-content.
Some Taoist wisdom here: conserve your jing (semen): be celibate. At your age, it is easy to calm your mind but the jing essence (life force) is already low. If one elder manages to reach the higher stages and then loses the sila of celibacy (due to increased sexual desire), then one can die due to one's higher energetic state. Conserve jing.
(Buddha says the same thing but smartly does not go into the energetics of it because people will focus on that too much.)