[Galatians 2:8 KJV] "(For he that wrought effectually in Peter to the apostleship of the circumcision, the same was mighty in me toward the Gentiles:)"...........The verse says Paul's apostleship was to the Gentiles and Peter's was to the Jews.
That's what took place due to time, place and circumstances, individually the places both had to be generally stationed, minister and witness for the Kingdom of GOD.
And moreover is merely an 'out of context' point of view and statement on your part cum 'addition', even to singularly hold on to what Paul just happened to confess one time.
But nevertheless 'in context ', and given the opportunity by Christ, they both did reach out, Peter to the Gentiles and Paul to the Jews.
Also they both received revelation individually to minister and witness to whichever group they were sent to, or remain with for a time.
That is because again 'in context' this comes in-line with the actual calling and commission the Master Jesus Himself chose and given them, whilst sending them. (2Timothy3:16&17)
Dough and Fred J. are not right and truth, coz we're men and possibly lie in ignorance or forgetfulness.
But rather, All Scripture=Holy Bible in context and sound doctrine intact, is 'right' and the 'truth' to reckon with.
The Gentiles were saved in Acts 10 from Peter's preaching. but the Gentiles were saved by a different gospel than what Paul preached...................Peter preached forgiveness by the name of Jesus, not his death and resurrection to save all.................[Acts 10:43 KJV] "To him give all the prophets witness, that through his name whosoever believeth in him shall receive remission of sins."
Again, out of context opinion and statement repeatedly about 2 different Gospels, for it's absurd and undermining the scripture in context.
To make it 'short and simple', as per context, before Paul became born again apparently happened in the 'middle' of the book of Acts.
The chosen 12 disciples beforehand were already commissioned since Christ around, to likewise make disciple of all nation.
Therefore way before Paul, the Gentiles were already being ministered and witnessed and discipled by the Gospel the Apostles held.
By this many Gentiles already came to faith and the Apostles would have already established Gentile churches as well, again way before Paul.
And when Paul came into the picture in ministry, he gave Gentiles extended revelational 'insight' in addition to the initial Gospel they already know.
'Common sense' teaches us why Paul suddenly was sent into the picture to preach another gospel to the Gentiles confusing them?
Apparently this would be the mistake of Christ 'messing up' in the first place, is that even sensible to hear?
For the benefit of the doubt, Paul's Gospel to the Gentiles only made it until Rome, but the Gospel from the 12 Apostles beforehand to the Gentiles, even made it until the ends of the earth.
Historical facts are there even in social media, what happened to the 12 Apostles of Christ and nations they ended up as martyrs.
To conclude, it is 'common sense' even scripturally and spiritually, that there is 'one' Gospel in context, even in the New Testament.
Shalom in the name of Lord Jesus Christ