Mostly modern/showbiz if you're into that
https://www.mangago.zone/read-manga/for_the_musical_genius/
https://www.mangago.zone/read-manga/the_genius_actor_s_aura/
https://www.mangago.zone/read-manga/regressor_s_life_after_retirement/
https://www.mangago.zone/read-manga/in_this_life_the_greatest_star_in_the_universe/
Took a look at your reading lists to check if you wanted action webtoon, seems not? So
https://www.mangago.zone/read-manga/once_again_idol/
https://www.mangago.zone/read-manga/this_is_the_law/
https://www.mangago.zone/read-manga/this_life_starts_as_a_child_actor/
https://www.mangago.zone/read-manga/life_once_again/
https://www.mangago.zone/read-manga/my_younger_sister_was_a_genius/
https://www.mangago.zone/read-manga/don_t_say_you_love_me/ BL
https://www.mangago.zone/read-manga/king_of_drama/
https://www.mangago.zone/read-manga/1st_year_max_level_manager/
https://www.mangago.zone/read-manga/i_became_a_sales_prodigy/
https://www.mangago.zone/read-manga/the_second_life_of_an_all_rounder_idol/
https://www.mangago.zone/read-manga/judge_lee_han_young/
https://www.mangago.zone/read-manga/be_the_actor/
https://www.mangago.zone/read-manga/acting_genius_top_idol/
https://www.mangago.zone/read-manga/da_capo_1/
https://www.mangago.zone/read-manga/rookie_employee_kim_cheolsu/
https://www.mangago.zone/read-manga/i_became_the_youngest_top_idol/
In case action/ shounen are okay too, this is good for starters
https://www.mangago.zone/read-manga/worn_and_torn_newbie/ mc is shrewd & hilarious
https://www.mangago.zone/read-manga/rescue_system/
If you want more, try my tag (mostly action/ shounen though)
https://www.mangago.zone/people/tag/24030/reincarnated+to+his+own+life/
Please recommend some manhwas where male MC’s isekai-d or regressed. Thanks a bunch!!!