Hi, I'm back.The plant in the middle of your first picture goes by the common name of annual mercury, and the scientific name of Mercurialis annua. (All plants have at least two names. They can have any number of common names, which vary from language to language, country to country, and five gardeners in one street may know the same plant by five different names. The scientific name is one which the top people in the world of plant science have agreed to call it, and even they change their minds sometimes. By convention, scientific names are either written in italics or underlined. Don't let any of this bother you, some of the best gardeners are illiterate.) I agree with Dovefromabove about the Eschscholtzia, also known as California poppy, which a lot easier to spell. The other plant that appears in most of your pictures is, I think one of the speedwells; does it have blue flowers? There are several species of speedwell which look and behave much alike. Try googling Veronica hederifolia, V. chamaedrys or V. persica if you're bothered to know which. A sharp hoe is your best friend for controlling weeds. They can't usually be eliminated completely. Hoeing regularly between the plants that are meant to be there will remove the top growth, and if you do it often enough, the roots will give up and die. Compared to weedkillers, hoeing is cheap, and does no harm to children, pets or wildlife.Have fun in your garden, and come back to the forum as often as you like, there are no silly questions. We all had to start somewhere.
Is this one in the second picture maybe a euphorbia...?
Everlasting sweet pea