Any BLs where they’re over protective or doting that it’s borderline possessive or obsessive?
https://www.mangago.me/read-manga/the_dreaming_trainer_s_ideal_master/ the first couple, also there's more like that, can't recall the title tho
Any bl where the ml is crazy obsessed or possessive and the uke is into that or equally crazy?
red mansion
this one is pretty popular so you've probablu already read that one lol https://www.mangago.me/read-manga/it_s_all_your_fault_that_i_m_being_a_jerk/
It's where the seme didn't want to commit, no matter how hard the uke tried. The seme even said he wouldn't draw the uke because he wasn't pretty. Then when the seme actually fell in love with the uke, the uke no longer liked him (the same happened in his past relationship). There was also a catus.
Pretty sure it’s sand castle: https://www.mangago.me/read-manga/sand_castle/

Give me [single or a list] of gl you think it’s good for a first time reader. If that’s too broad of a criteria, here’s some genres I think I would like (but I’m down to explore beyond these):
Give me some angst, but please not too heartbreaking with a sad ending. It’ll be my first read, so don’t make it my last.
Or are there any historical comedic gl ones? I think I’d be down for those too. If there’s a whole list, even better.
The Guy She Was Interested in Wasn't a Guy At All- https://www.mangago.me/read-manga/the_guy_she_was_interested_in_wasn_t_a_guy_at_all/
Onna to Tabetai Onna- https://www.mangago.me/read-manga/tsukuritai_onna_to_tabetai_onna/
Here goes a list of titles I would recommend to you for different reasons:
Haven't read, the ones that are on my list for reading and I'm eager to read because everything about the story initially attracts me:
-Crossing the Line of Love
-Your Head’s Fallen Off Again
-Kiss the Coming Apocalypse
-in to the sea
-Perfect Heroine Wants to Possess Me
-The Wind Spell
-My Dear Lass
-Soulmate
-Hummingbird Effect
have read and I know they kinda fit your description:
-murmur
-blood time
-bead master
-her mountain, her ocean
-kill switch
-bad thinking diary
Reading right now and I think they have potential:
-she is also cute today
-falling
-fatal possession
-long awaited feelings
-moonlight garden
-relationship guidelines
-i think you are-
Anyways some of this contain smut and other don't, so check out some of the titles and select the ones you find suit you best!!