For professional email I recommend firstname.lastname@domain because it’s very common and lets people almost uniquely identify you from your email address alone. You could also register a domain such as lastname.com such that you can use [email protected]. Just make sure to use a reputable email host to make sure that your emails don’t end up in spam.
Even if you can’t afford Nebula, I recommend browsing its explore section, because many of its high quality creators and videos are also on YouTube. The following are some of my favourite creators on YouTube.
30 minute animated documentary-style videos: LEMMiNO, melodysheep, fern, Hoog, neo, PolyMatter, Imperial, Cipher, Real Engineering, Mustard
Shorter explainer videos: Posy, Kurzgesagt, PBS Space Time, Sciencephile the AI, minutephysics, Steve Mould, Half as Interesting
Hetzner has some really cheap servers in Germany
I use Raccoon because it’s open source and implements Material Design