I dunno about Solo, it would have artificial flavours and colours in it so you wouldn’t really get the same flavour from fresh lemons. But an alternate idea, you could look up recipes to make lemon cordial. Then mix with soda water to make a fizzy lemonade drink. Delicious!

https://www.hillbillyhousewife.com/site/lemonade.htm

Also maybe lemon meringue pie? I actually found the old recipe I used in my teens. But it might be more efficient just to make a large amount of the lemon filling only, or lemon butter. That's easier to store in jars and could use more lemons

Edit: I had issues uploading the saved jpgs

Do you want soft or hard? I suppose my hard recipe would be ok without the yeast, but probably not last as long.

We use this one, not fizzy but you could add soda water if you want. traditional lemonade