Liin "Tera" Terallo
Firstly; welcome!
Secondly, about making a political character. From my experience the best political RP comes from the angle of building something from nothing. A policy point, a foundation perhaps, even relationships between other characters. I would start off "small" and let the RP progress your character's importance organically.
Not only will this help legitimize your character's powerplays or endorsements because people have seen you've put in the work & time via character progression but it will also allow you as a new political character to build bonds In Character in a unique way. Political characters really do sink or swim by how willing other players are to accept their proposed influence on events. Anyone can throw on an Emperor tag and rule sectors full of planets of NPCs to do their bidding but that seems shallow to most (in my experience). Starting off lower and then spending time in the political trenches so to speak, helps sharpen your own knowledge about your character's motives & operating standards but also allows others to passively accept a rise to prominence.
Some of the most well received political characters started as pretty low on the totem pole and worked their way up which includes (non exhaustive list mind you, many people have been very hard workers):
Annasari
Auteme
Aerarii Tithe
I'd encourage you to look over their character sheets and their posts. Annasari, Auteme, and Aerarii Tithe have all be the Chancellor (political top dog) for the Galactic Alliance which has a very large political character base. They are some of the best writers when it comes to long term political RP.
This character, Sssar, started off as the senator of the smallest 'planet' in the Alliance. While he never went very far in terms of importance he had a long history in the Senate which allowed a certain level of respect from some other senate writers which was really rewarding for me as a player. To see my senator go from a political nobody from a backwater station, almost entirely forgotten about, to a character that was well received & acknowledged as a mainstay of the IC lawmaking body.
If you have an interest in political RP I'd highly recommend the Galactic Alliance as a start. There is nothing preventing your character from changing factions or going their own way. Though from my standpoint I'd say there are few places more established for political/diplomatic RP.