I didn't read the OP asked for Electrum mobile version where coin control is a bit more complicated (I rarely use the mobile app for real "money") and maybe missed most recent changes. What I remember for the mobile version of Electrum is, that you have to freeze all coins or addresses you don't want to spend from, instead of selecting stuff for coin control, but this maybe changed in most recent versions of the mobile app. Don't nail me for it.
As im busy right now I had no time to read the manual and just lazily asked GPT, but AI sucks ...
LOL, that's a neat excuse for not having to research yourself. I've seen you ask a lot of questions here and there over the past that could be answered with some (little search) effort of your own, but that's another story, maybe old gossip...

In desktop's Electrum in the Addresses tab you can select single or multiple addresses with funds, right click and select "Add to coin control" from context menu. You don't have the context option of "Add to coin control" when addresses don't have any funds, i.e. doesn't show up with "empty" addresses.
If you want coin control on the UTXO level, you do the same on the Coins tab. Quite well described by the AI output you cited. I don't know that you didn't understand there, frankly.
If you don't see those tabs by default, open "View" menu and enable those.