Usually, when I plant plants, I put a nameplate next to it. I'm not very good at botany ... But once my dogs played into the garden and pulled out and mixed up all the nameplates ... Now there is no sense from them ... And now in the spring I sometimes don’t know if it is a flower or a weed ... My friend advised me to photograph such plants and find them in Google. I did so. But now I can’t find some of them in the garden ....
There are even some apps that work very well if you want to know about the name or even it tells you if you lacking something like fertilizer or it is watered less.
iNaturalist is good. Just mark it as cultivated if you make an observation. It has an AI that suggests you what species it could be. It works for all the common plants.
Last one looks like Artemisia. Possibly Artemisia absinthium.