As someone looking into Catholicism, you should definitely have a copy of the Catechism of the Catholic Church. It can be found for free online as well:
usccb.org/beliefs-and-teachings/what-we-believe/catechism/catechism-of-the-catholic-church/
This book contains official Catholic doctrines on practically everything. Here are some relevant excerpts for you:
Priesthood of All Believers
*
1546 Christ, high priest and unique mediator, has made of the Church "a kingdom, priests for his God and Father."20 The whole community of believers is, as such, priestly. The faithful exercise their baptismal priesthood through their participation, each according to his own vocation, in Christ’s mission as priest, prophet, and king. Through the sacraments of Baptism and Confirmation the faithful are "consecrated to be . . . a holy priesthood."21
1591 The whole Church is a priestly people. Through Baptism all the faithful share in the priesthood of Christ. This participation is called the “common priesthood of the faithful.” Based on this common priesthood and ordered to its service, there exists another participation in the mission of Christ: the ministry conferred by the sacrament of Holy Orders, where the task is to serve in the name and in the person of Christ the Head in the midst of the community. *
The Ministerial Priesthood
*
1555 "Amongst those various offices which have been exercised in the Church from the earliest times the chief place, according to the witness of tradition, is held by the function of those who, through their appointment to the dignity and responsibility of bishop, and in virtue consequently of the unbroken succession going back to the beginning, are regarded as transmitters of the apostolic line."34
1556 To fulfill their exalted mission, "the apostles were endowed by Christ with a special outpouring of the Holy Spirit coming upon them, and by the imposition of hands they passed on to their auxiliaries the gift of the Spirit, which is transmitted down to our day through episcopal consecration."35
1557 The Second Vatican Council “teaches . . . that the fullness of the sacrament of Holy Orders is conferred by episcopal consecration, that fullness namely which, both in the liturgical tradition of the Church and the language of the Fathers of the Church, is called the high priesthood, the acme (summa) of the sacred ministry.”
1560 As Christ’s vicar, each bishop has the pastoral care of the particular Church entrusted to him, but at the same time he bears collegially with all his brothers in the episcopacy the solicitude for all the Churches: “Though each bishop is the lawful pastor only of the portion of the flock entrusted to his care, as a legitimate successor of the apostles he is, by divine institution and precept, responsible with the other bishops for the apostolic mission of the Church.”
1562 "Christ, whom the Father hallowed and sent into the world, has, through his apostles, made their successors, the bishops namely, sharers in his consecration and mission; and these, in their turn, duly entrusted in varying degrees various members of the Church with the office of their ministry."43 "The function of the bishops’ ministry was handed over in a subordinate degree to priests so that they might be appointed in the order of the priesthood and be co-workers of the episcopal order for the proper fulfillment of the apostolic mission that had been entrusted to it by Christ."44
1563 “Because it is joined with the episcopal order the office of priests shares in the authority by which Christ himself builds up and sanctifies and rules his Body. Hence the priesthood of priests, while presupposing the sacraments of initiation, is nevertheless conferred by its own particular sacrament. Through that sacrament priests by the anointing of the Holy Spirit are signed with a special character and so are configured to Christ the priest in such a way that they are able to act in the person of Christ the head.”
1569 “At a lower level of the hierarchy are to be found deacons, who receive the imposition of hands 'not unto the priesthood, but unto the ministry.”'53 At an ordination to the diaconate only the bishop lays hands on the candidate, thus signifying the deacon’s special attachment to the bishop in the tasks of his "diakonia."54
1570 Deacons share in Christ’s mission and grace in a special way.55 The sacrament of Holy Orders marks them with an imprint (“character”) which cannot be removed and which configures them to Christ, who made himself the “deacon” or servant of all.56 Among other tasks, it is the task of deacons to assist the bishop and priests in the celebration of the divine mysteries, above all the Eucharist, in the distribution of Holy Communion, in assisting at and blessing marriages, in the proclamation of the Gospel and preaching, in presiding over funerals, and in dedicating themselves to the various ministries of charity.57 *
