Forgotten Title (+ Forgotten titles) A call to Manga/hwa/hua readers who've read works from pre 2012

Hi everyone, i started reading mangas back in 2011/12 when most korean and chinese works used to be published in manga format. I was really into romance genre so i must've read almost everything that wasn't tragedy from that time period. ie (pre 2012 works). so i wanted to call upon some veterans or those who have read earlier works. My Mangarock app used to be stack with favourites but i deleted the app not long ago and now i don't think i can retrieve the titles.
so i wanted some help to identify the many titles I've read over the years and only vaguely remember from the plot and character descriptions.
I would also like to discuss the old school mangas with some enthusiasts. for example I've read a ton of Hwang Mi-ri and Han Yu Rang, while a lot of them tend to be over the top but i'm more understanding and accepting of character plot and believability as long as it's not pure nonsense. they comprise a large part of my teenage years so reminiscing and discussing such titles would be great fun too. (I'm not sure if such a thread already exists but i'm not good with the site and my searches never show up)

(Following is a list of manhwas, which after my description will sound utterly bland) THERE MAY ALSO BE SPOILERS AHEAD in trying to describe.
1) I think it was called something like citrus orange or on those lines (but i can't seem to find it). high school students, there's a boy that falls in love at first sight with a beauty from another high school. He confesses to her lots of time but keeps getting rejected. (she eventually agrees later out of pity). Her ex-step brother is kinda always on the lookout for her and she mostly hangs out with him.

2) it involves 6 people based in one school. the MC is a nerdy girl who's trying to study hard for college. she has a crush on the school president who kinda seems to like her a bit too? but there's lots of pressure from the family to study well. there's a bad boy who barely comes to school like the delinquent and the mc and him somehow end up hanging out. then there's a half chinese girl who's a new admission, she used to be a model i think? and a gamer boy who falls in love at first sight with her i think. there's also the young teacher (woman).

3) this one i'm so on the verge of remembering the title. the MC is the female teacher at an i think an all boys high school. she's kinda in a relationship with another male teacher. then there's this boy who if i remember correctly is a lonely rich kid. kinda troublesome and he is subtly seducing the MC. it's kind of a psychological manwha . [SPOLER: they kinda get together towards the end but he disappears]

4) this one I had read once after finding it somehow so i believe not many people would know of it. i think they're 3 independent ladies. the focus is on romance and work life. for the main girl she reconnects with her old sunbae i think from college? i think she used to have a crus on her. he rich and handsome. they start dating. she is a fashion designer i think and works in a company headed by the female CEO who's unmarried. POTENTIAL SPOILERS she wants to make her the next CEO of the company but there's the life family issue. while the boyfriend wants to marry her but i think theres some talk about leaving work? or that if she takes up the CEO position she will not be able to focus on a family. [in the end since he really wants her he says that he does't care he's willing to raise the kids by himself too haha]
i don't remember the stories of the two other girls. i think one was her neigbour she befriended eventually.

There might be more but i think i'll start with these if i'm lucky enough to get help (i'm also attaching random tags)