Thanks a lot everyone, especially @Eggcessive and @Trisseh the medicinal honey and warm water worked well and he has recovered 90% . He can walk properly now. Thanks a lot everyone for help.
Rain is not pink he just got the color on him cause he sleeps with bow(another one). The seller had dyed each of its chicks some were even green and purple.
He managed to creep in the kitchen to find some food, while roaming in the backyard. I don't know how he went unnoticed from me. As soon as I saw him in the kitchen I tried to catch him but he jumped in the oil... luckily he jumped out without a seconds delay.
1. Only one of them is pink , it was dyed by the seller.
2. They were roaming in the backyard, but somehow rain(name of the chick) managed to creep in the kitchen.