First...v. 1-8- an impressive run on sentence.

From the ESV study notes:

One remarkable feature of this section is that many of the themes mentioned here also conclude the letter in the final doxology (16:25–27):

(1) Paul's apostolic authority;
(2) the fulfillment of the OT Scriptures in the gospel;
(3) the gospel that centers on Jesus Christ;
(4) the obedience of faith;
(5) the mission to the Gentiles; and
(6) the glory of Jesus Christ and God the Father.

Also, (R. Kent Hughes).
Paul’s view of himself (v. 1)
Paul’s view of preaching (vv. 2–4)
Paul’s view of his commission (v. 5)
Paul’s view of the Roman believers (and us) (vv. 6, 7)

On to the passage:

1 Paul, a servant of Christ Jesus, called to be an apostle, set apart for the gospel of God,

"Servant" is doulos - slave. Slave f Christ, appointed to be an ambassador, marked off by God to preach the gospel.

Slavery to Christ is a key theme that Paul chose for Himself...echoing Christ, Mark 19:45

For even the Son of Man came not to be served but to serve, and to give his life as a ransom for many.”

Paul elaborates, and confirms his mission to the Gentiles in Galations 1:15-16

But when he who had set me apart before I was born, and who called me by his grace, was pleased to reveal his Son to me, in order that I might preach him among the Gentiles,

2 which he promised beforehand through his prophets in the holy Scriptures,

God's prophets promised this good news long ago.

3 concerning his Son, who was descended from David according to the flesh

Fully God, fully man.

4 and was declared to be the Son of God in power according to the Spirit of holiness by his resurrection from the dead, Jesus Christ our Lord,

It was the Spirit who bore witness to the deity of Christ, through His resurrection.

5 through whom we have received grace and apostleship to bring about the obedience of faith for the sake of his name among all the nations,

This mission of Paul's is an act of grace.

6 including you who are called to belong to Jesus Christ,

Election is just all over the place...

7 To all those in Rome who are loved by God and called to be saints:
Grace to you and peace from God our Father and the Lord Jesus Christ

We are called by God,
We are loved by God,
We are saints of God,
We are the recipients of God's grace and peace...