Lightning: Open Channel, Sign, Broadcast, Remove. What is all of this?

I'm used to normal BTC, but I just wanted to make a donation, and found out they only supported Lightning, so I decided to convert some with my Electrum wallet. I had very little knowledge before, but over some events, things got confusing, so I ask for a more complete answer to try to understand better what is happening.

I had opened a new channel, and it selected "Electrum trampoline" as default, so I kept it as is, I selected the amount of BTC _(I read that there is a minimum value? But it was a bit over 0.003BTC, so I think it should be fine)_

I thought that was it, and nothing changed, I assumed maybe the fees weren't high enough, but I saw the button to `Sign`, and thought it could be required, so I did it, and things changed, but then it asked to broadcast.

One thing I had read was that for lightning to work, you need both sides always online, and I left my phone there, but forgot about it, and when I saw it again, I noticed that it was talking about broadcasting it again, or to delete the request.

I then remembered of the always on rule, and guessed it didn't go ahead after all, so I considered just removing the transaction and trying again with a higher fee to get things faster (I usually have no haste in my transactions).

And after removing, the transaction doesn't appear anymore in my list, however, there is a "Lightning balance" there. At first I panicked as I thought that my main balance had its funds removed, but after manually summing all values, it seems that wasn't the case, so my "Total Balance" is now the sum of my proper "On-chain" balance and a value in Lightning that supposedly doesn't exist.

So before trying again, now I want to ensure proper understanding of the limitations if someone could kindly explain it.

Edit:

I found a bit more of information through the option "Channels" in the left menu, then I found out the channel I had created even though I closed the request, and there I could properly shut it down and so on.

Also found out a bunch of rules, such as that you can't receive Lightning in your open channel (that acts like a wallet) until you spend some of it.

From what I read, you need to spend to be able to receive ,although just as much as what you spent, so without having used it yet, I'm guessing the channel you open is basically the largest amount of BTC you can get in the Lightning network, although I'm likely wrong, as if that were the case, it would have been impossible to make a first transaction.

Anyway, At least I found that I had indeed spent some bitcoins on that failed try, and that I could get them back.