Hangul ᄀ = G/K and ᄁ = kk
The letter (giyeok ) ᄀ can be pronounced like a G or a K depending on where it is in a syllable. The ᄀ can also look different, for example it can look like ᄀ or ᄀᅠdepending on where it is in a syllable.
If it comes on the side of a syllable it will be curved and if it is on the top or the bottom of a syllable it will be in its original form. Some examples show the variations:
기 (gi), 길 (gil), 김 (gim)
Study words that start with ᄀ on TinyCards – a Duolingo site.
ᄁ= kk
The second letter of the Korean alphabet is the letter ᄁ (ssanggiyeok ). It is a doubled giyeok ᄀ . It is pronounced with a harder kk sound thanᄀ.
See KoreanWikiProject for example syllables withᄁ.
Read through more Hangul Lessons. You can also look at resources to learn to read Hangul.