u/SnailClops

I've just gotten into building my website and ive been doing great so far with html learning resources (w3schools my beloved <3)
but i cant for the life of me figure out how to make these boxes? or how to centre my site so that everything is in the middle

https://preview.redd.it/ezagkb48n32h1.png?width=629&format=png&auto=webp&s=d1469259b696753fcd6efe45612421bb8eadbc4f

I drew what i mean here for the boxes ^^^
and here's some websites as examples of what i mean

https://preview.redd.it/n08nlc9in32h1.png?width=1906&format=png&auto=webp&s=c2222689e26e810baf99472888598da65af43fde

https://preview.redd.it/zy8xhixmn32h1.png?width=1880&format=png&auto=webp&s=854c34b21b00dd02c72e369c87e39113b8d1d0f2

https://preview.redd.it/lw64mr4pn32h1.png?width=1873&format=png&auto=webp&s=01ddfe6b69c40c2791c17c8dd1a5b709332e542a

https://preview.redd.it/qax7xl2gjj0h1.png?width=472&format=png&auto=webp&s=5c3bff4cc8bcb96370c41e54132c882821724824

a user on tumblr (llegato) has it as his pfp but doesn't know where its from so wondering if anyone here knew?