For canning, it's very important to use tested recipes from reliable sources. These recipes seem okay to me except for one instruction in the first one - it says to screw the rings on tightly. In order to create the vacuum seal that helps make canned goods shelf-stable, the bands need to be just finger-tight so air can escape during processing. I have no idea how much experience the OP has, but I wanted to mention it.I found a recipe for blueberry jam AND another for blueberry jelly.
The lemon comes in with the addition of 1 teaspoon of lemon zest and ⅓ C of lemon juice. Seems like you could combine parts of the two recipes to get what you want.
https://www.myfoodandfamily.com/recipe/221410/surejell-blueberry-jelly
https://www.food.com/recipe/blueberry-lemon-jam-118236
I hope this helps.