You are not alone Soc. You have two millennia of Christianity with you.
Who soon developed awareness of this chicken and egg dilemma you so clearly explain and live at present, about trusting an authority to reach the truth versus reaching the truth to trust an authority.
Hence what are called marks or notes of the Church.
Among these, apostolicity was early developed and explained.
Let’s read this one.
*1. It is within the power of all, therefore, in every Church, who may wish to see the truth, to contemplate clearly the tradition of the apostles manifested throughout the whole world; and we are in a position to reckon up those who were by the apostles instituted bishops in the Churches, and [to demonstrate] the succession of these men to our own times; those who neither taught nor knew of anything like what these [heretics] rave about. …
.2. Since, however, it would be very tedious, in such a volume as this, to reckon up the successions of all the Churches, we do put to confusion all those who, in whatever manner, whether by an evil self-pleasing, by vainglory, or by blindness and perverse opinion, assemble in unauthorized meetings; [we do this, I say,] by indicating that tradition derived from the apostles, of the very great, the very ancient, and universally known Church founded and organized at Rome by the two most glorious apostles, Peter and Paul; as also [by pointing out] the faith preached to men, which comes down to our time by means of the successions of the bishops.
For it is a matter of necessity that every Church should agree with this Church, on account of its preeminent authority, that is, the faithful everywhere, inasmuch as the tradition has been preserved continuously by those [faithful men] who exist everywhere. * Irenaeus, Adversus Haereses, Book III, ch. 3. About 180 AD
I think this passage deserves your meditation at this point.
Christianity went on reflecting on the notes of the Church. This was necessary, because in early times there appear to have been … many Eds, proposing diverging doctrines against the apostolic Church as well as against each other.
I do not know whether in your former branch of Evangelicalism the Creed of Nicea had been preserved or at least partially rejected.
What is stated there about the Church built by Jesus are four marks
- One
- Holy
- Catholic
- Apostolic
In order to avoid obvious issues on oneness and catholicity about their newly settled religious bodies, most of which would accept the Creed, from the beginning protestant teachers had to develop the theory of a merely invisible catholic Church, as we already saw in your previous thread.
Then, about apostolicity, the traditional objective dimension of legitimate succession was, once again out of necessity, fully rejected.
And protestantisms dismantled this way these ancient tools permitting to avoid our present chicken and egg dilemma.
We all ask what is Jesus’ Church, in order to know where the orthodox message can be learnt by us.
Protestant brothers often simply tell me that …… Jesus’ Church, is where the purest orthodox message can be learnt by us,

ie ……that particular expression of the invisible catholic Church which is represented by their own faith community.
I hope something in these two posts can help, Soc.
In Christ
P7