When I started with a team that did Agile and I didn’t, I learned Agile.
When I started with a team that used TypeScript and I didn’t, I learned TypeScript.
This doesn’t mean I didn’t throw in my own suggestions or bowed down to what was there but it did mean I learned the systems that were in place that had made that team successful. Along the way, I made suggestions for them and us to improve as a whole.
Coming into an existing team, there is a dynamic, a flow, that has already been established, unless you’re there to fix it and reset it, you need to work with it and affect change from within.
But before you suggest those changes, you need to understand why the team is here, why they made these decisions, and what shaped them and brought them to this point. Unless you’re being brought into blow it all up, you won’t get far without learning why they are here to begin with.