This is the 2015 Korean youth/romance/comedy drama series. Its native title is "응답하라 1988" and it's also known as "Answer Me 1988," "Respond 1988," "Answer to 1988," and "Respond to 1988."

From MyDramaList: https://mydramalist.com/13544-reply-1988
"Five childhood friends, who all live in the same Ssangmundong neighborhood of Seoul, lean on each other to survive their challenging teen years and set a path for their futures. Sung Deok-sun struggles for attention as the middle child in her poor family while also carrying the burden of her 999th ranking in school. Kim Jung-hwan only has a one-track mind for soccer, even after his family becomes rich overnight. Sung Sun-woo is the perfect student, student council president and a caring and dependable son in his family. Ryu Dong-ryong is a geek who knows more about girls and life than the rest of his friends, but his poor academic score prevents him from being able to go to college. Choi Taek is a genius Go player who dropped out of school to go professional. As the group of friends gets into and out of mischief around the neighborhood, what experiences from these memorable times together will they carry with them into their future lives?"

IMDB: https://www.imdb.com/title/tt5182866
AsianWiki: https://asianwiki.com/Reply_1988

This is the complete set of 20 episodes ranging from 75 to 113 minutes long each. They all have edited "soft" English captions; that is, English subtitles are part of the MKV file and the subtitles can be enabled or disabled as you wish.

I downloaded the source videos named like "Reply.1988.E01.1080p.NF.WEB-DL.DDP2.0.x264-deeplife [DRAMADAY.me].mkv" and extracted the English subtitles from them. Then I...
- Used Subtitle Edit (by Nikolaj Lynge Olsson) to find and fix all flagged issues
- Watched the series and italicized music lyrics, characters' thoughts, short flashbacks, and some off-screen dialogue; also color-coded some subtitles for clarity as appropriate, using yellow, teal, and salmon colors for signs, flashbacks, and written/printed material respectively
- Added 0.7 second to each subtitle (where possible) to allow more time to read them and adjusted words/minute to at least 280
- "Softened" all subtitled profanity (bastard --> jerk, damn --> darn, bitch --> witch etc.)
- Corrected commonly-found typos, converted many word pairs into common English contractions, brought together sentence fragments, removed unnecessary translated words like "oh" and "ah", etc., converted Korean Won amounts into American Dollars, converted British terms to American ones, and (where needed) converted Korean names to AP style (family name followed by hyphenated given name)
- Split up and/or rewrote lengthy and/or wordy subtitles to maintain 23 characters/second and/or 280 words/minute or less
- Used Handbrake to create new MKV files using my subtitles

Format: MKV
Format info: Audio Video Interleave
Total file sizes: 36.2 GB (38,897 MB)
Total duration: 31 hours, 36 minutes, 55 seconds
Overall bitrate: 2728 Kbps

Video format: MKV
Video Codec: H264 - MPEG-4 AVC (part 10) (avc1)
Video bitrate: 2600 Kbps (2-pass)
Video width: 1920 pixels
Video height: 1080 pixels
Video frame rate: 23.976 fps
Video decoded format: Planar 4:2:0 YUV
Video scan type: Progressive

Audio format: MPEG AAC Audio (mp4a)
Audio language: Korean
Audio bitrate mode: Constant
Audio bitrate: 128 Kbps
Audio channel(s): 2
Audio sampling rate: 48 KHz 

Subtitles:  English as soft captions - feel free to rip & use or distribute as you wish