I run lubuntu in my ~#missing#~. I have made multiple efforts to install umbrel, I tried it but I couldn't install to my external SSD because I run out of space. I used all the possible commands but with no success. I need another software for my lubuntu to build my node without buying more hardware if that is possible.
Mh yes, this is one of the tricky parts of the lightning network! Sorry about that
In my early years, I worked on this problem and how to solve it with core lightning, and I came out with a solution that used the https://github.com/clightning4j/btcli4j plugin to fetch the bitcoin data in a different way (including the Rest API, so you do not need a bitcoin node)
You can find the description in my article that uses the docker to run all the architecture https://github.com/clightning4j/clightning4j-node
Otherwise, if you want to run core lightning without docker, you can just install the plugin and run it with the command
lightningd --disable-plugin bcli