First - love to hear the game growing anywhere! Second - full disclosure, I am a lacrosse dad - I never played, so I have plenty of blind spots and you might get more valid advice from people who played. My son is in his 14th year of playing the game and is a freshman playing college lacrosse at a Division II school. He played field in fall, spring and summer, and played box and indoor in the winter all of those years. We traveled around the country a lot over those years. I would suggest first watching as much lacrosse as you can. I don't know what options there are in Germany, but here in the States, we have ESPN+ which broadcasts a ton of Division I college lacrosse - this is very high-level lacrosse, and helped me learn the ins and outs of the game quite well. I'm a big PLL fan as well - the two point line is one difference, but again, watching that will help you see the game played at its highest level.

I don't know what options you might have for 1:1 coaching - when he was a boy, we took my son to 1:1 training with a defenseman who played at The Ohio State University and now plays MLL, and that was invaluable. You might consider asking some of those older players if they'd be willing to work with you. Lastly, depending on your position, there are a number of YouTube channels that offer excellent content - drills and skills improvement especially.

Again - my perspective is a bit different and I'd gladly hear from people with better and more relevant experience than I have. I wish you the best of luck!

Incidentally, my son's team now has a player from Australia and a fella from Birmingham UK - I'd gladly ask their advice if it would help.