Almost certainly not. กินข้าวหรือยัง (literally 'eat rice or not yet') is a greeting, roughly where English puts 'how are you'. It is asked at times of day when nobody could be about to offer you a meal.
The expected answer is not a report on your appetite. กินแล้ว (eaten already) or ยัง (not yet) closes it, and the conversation moves on.
- กินข้าวหรือยังkin kʰâːw rɯ̌ː jaŋ
have you eaten yet?
a greeting, not an invitation
- กินแล้วkin lɛ́ːw
eaten already
the safe answer
- ยังjaŋ
not yet
also fine: it does not commit you to anything
The useful part
ข้าว is rice, and it is also food in general: 'eat rice' means 'eat'. That substitution runs deep enough that you will meet it constantly, and it is worth noticing early rather than being puzzled by it for a month.
In polite company ทาน replaces กิน. Same meaning, softer register; use it with anyone older or senior and you will sound considerably better brought up.
- ทานtʰaːn
to eat (polite)
swap it in for กิน when speaking to someone older