Most of my project involved reading, well about 90% was reading and trying to work out if what I had just read was from Openhab v1 or from v2 and if it was v1 was it still relevant in v2. I am no coder / programmer My first language is English and I even struggle with that at times, where wear and Openhab is just as bad, It`s neither Basic or python but seems to be a bit of both.
I am a tinkerer ( I can take something and twiddle/hack/break it and try to make it do something else, right now I am abusing my 3D printer by taking the print head off and putting a motor and cnc bits in its place too cut/ cnc mill single sided pcbs),
I started off by looking at the code in Hestiapi and trying to figure out what it done ( the folder structure on HestiaPi is well different from other versions of openhab, ie openhabain etc but once you start to find your way round the files that you can change/add then it becomes a LOT easier).
Adding another sitemap with my weather data (I used yahoo weather first so I could learn how to change things ** lots of reading the docs and forums at Openhab** looking for others sitemaps etc) then once the setup is happy just tweak the graphics via the web interface
It will all fall into place. If you have a small grasp of python from tinkering with a Pi then you should be on the road to getting to grips with HestiaPi and Openhab 2.
I would send you an Image but I have an annoying bug that crashes the pi, so at the moment it is on the back shelf as other projects are on the go, I will get round to looking back into it later in the year when it starts to cool down and I need the setup to work as is should. Also just using the image you would not learn about changes that might need to be made.
I can I think maybe attach a couple of files that I have changed and added so you could compare them to the original files and that way it`s giving you a start.