Yes,
we all support ourselves on this forum with our experience, everyone has started their adventure with keyboards once.
@ "panos", all your tips mentioned above I also usually follow. Especially if I try to play new songs in a new key with many # ... b ... signs, eg Eb, Ab.
As a few years old amateur of playing the keyboards, I am still learning. If I was 7 or 17 as a teacher, learning would be more effective, based on a firmer foundation. Hand dexterity, understanding the basics of harmony, chord relatedness, chord progression. All this makes it easier to remember chord sequences.
After 6-7 years of studying a young person in a music school, you are already a professional, not an amateur.
But I did not notice that my grandchildren were eager to learn to play the keyboard. This is a hard science.
This also explains the reluctance of old amateurs who strive for the pleasure of playing without studying music theory and practicing. The point is to play a piece that is in your head from the old days as quickly and as well as possible. Then another song, one more, and so on. There are various difficulties and doubts along the way. The most important thing is to play, make sure your fingers remember that your brain can keep up with the pace, because the memory of your fingers is unreliable.
I've noticed that even professional musicians who play dozens of popular songs at parties usually play them in a few of the same key, major and minor. I think learning and remembering chord inversion in rarely played keys is much more difficult. There is no time to think when playing.
I recommend a book translated into many languages. At the beginning of my adventure with the keyboard, the book gave me a boost to learn, learning methodology, technical tips, and increased confidence. From the book you have to choose only what you need. Opinions about the book are full of admiration.
Fundamentals of Piano Practice
Chuan C. Chang's Home Page, Jan. 1, 2020
(PhD in physics from Cornell Univ., Ithaca, New York, pianist)
for Free Download of Complete Book
http://www.pianopractice.org/http://www.pianopractice.org/FOPP3_2Single.pdfThe book is also available on Amazon on paper.
"panos", now on the Baltic Sea we usually have Greek weather, so it's nice to spend time without being exposed to the hot sun. Spending time at an instrument or a computer.
greetings
Andy