Pīti is frequently misunderstood. (disclosure, my notes, my website) https://lucid24.org/sted/7sb/4piti/index.html In short, pīti as a jhāna factor and as one of the 7 awakening factors is the same exact thing. All 7 awakening factors are independent, can be done in any combination in any of the 4 jhānas and in any posture. Whatever physical bliss you experience is not actually pīti itself, but an effect of it. Pīti, like pamojjaa, is mental. In general, pīti is caused by the mental joy that arises when one is contemplating Dhamma thoughts, most notably the thought, "I can abide in bliss because my conduct is pure, my mind is clean, and I diligently exercise right effort and right mindfulness in purifying my mind at all times."

The physical joy, would fall under sukha, the direct byproduct of passaddhi / pacification awakening factor. That can be directly caused by pīti, or one can directly under the samādhi without vitakka (thinking) by simply relaxing (passaddhi/pacification) the body at any time, any posture.

Detail of passaddhi and getting into first jhāna here: (disclosure, my notes, my site) https://lucid24.org/sted/7sb/5passaddhi/index.html

Pīti means (mental) satisfied/"released", caused by renouncing-joy (withdraw from the cause of Dukkha, at first from holding on Sense-objects), effecting calm/stillness... with it sukha... by it unification/samadhi/going on/Jhana... seeing as it really works/does, ... disgust... non-desire ... release.

The lokuttara paṭiccasamuppāda (dependent co-arising of the path) is on and on displayed in the various ways and levels of the training, path.

In any case, Saddha/Sila, surrender (seeing the four Noble truth), will act as the basic for all to come a long by it's given cause.

Train Jhana for one not complete the first stage, Sila, doubtlessness, would neither, for the most, be Jhana nor would it lead toward the path. Hearing (reminded on) the Dhamma and proper attention causes right view.

Right effort, even if on the path, turn around the required causes: right view, right intent, right Sila/lifelihood. One Sila is rightly complete, joy (with oneself without faults) may be near to gain, when ever there is an opening.

Factors of awakening are total out of reach for one who has not attained stream.

First steps to gain a little bit of renouncing-joy, teaser if still not good in moral-virtue, is by making gifts, sacrifices toward those worthy for such (people with metta, Sila, Noble Ones). At least absence of stinginess of the five kinds, and absence of ingratitude, are requirements for Jhana and possible paths and fruits.

Very very unlikely that a stingy "modern Buddhist" will ever reach Jhana.

You can find some info in the Rapture (piti) section of "The Jhanas in Theravada Buddhist Meditation" by Ven. Henepola Gunaratana:

Rapture (piti)

The third factor present in the first jhana is piti, usually translated as joy or rapture. In the suttas piti is sometimes said to arise from another quality called pamojja, translated as joy or gladness, which springs up with the abandonment of the five hindrances. When the disciple sees the five hindrances abandoned in himself "gladness arises within him; thus gladdened, rapture arises in him; and when he is rapturous his body becomes tranquil" (D.i,73). Tranquillity in turn leads to happiness, on the basis of which the mind becomes concentrated. Thus rapture precedes the actual arising of the first jhana, but persists through the remaining stages up to the third jhana.

The Vibhanga defines piti as "gladness, joy, joyfulness, mirth, merriment, exultation, exhilaration, and satisfaction of mind" (Vbh. 257). The commentaries ascribe to it the characteristic of endearing, the function of refreshing the body and mind or pervading with rapture, and the manifestation as elation (Vism.143; PP.149). Shwe Zan Aung explains that "piti abstracted means interest of varying degrees of intensity, in an object felt as desirable or as calculated to bring happiness."

When defined in terms of agency, piti is that which creates interest in the object; when defined in terms of its nature it is the interest in the object. Because it creates a positive interest in the object, the jhana factor of rapture is able to counter and suppress the hindrance of ill will, a state of aversion implying a negative evaluation of the object.

Rapture is graded into five categories: minor rapture, momentary rapture, showering rapture, uplifting rapture and pervading rapture. Minor rapture is generally the first to appear in the progressive development of meditation; it is capable of causing the hairs of the body to rise. Momentary rapture, which is like lightning, comes next but cannot be sustained for long. Showering rapture runs through the body in waves, producing a thrill but without leaving a lasting impact. Uplifting rapture, which can cause levitation, is more sustained but still tends to disturb concentration, The form of rapture most conductive to the attainment of jhana is all-pervading rapture, which is said to suffuse the whole body so that it becomes like a full bladder or like a mountain cavern inundated with a mighty flood of water. The Visuddhimagga states that what is intended by the jhana factor of rapture is this all-pervading rapture "which is the root of absorption and comes by growth into association with absorption" (Vism.144; PP.151)