Need recommendations for formula milk

Hi! Ftm here. What’s the best formula milk for babies(3-4months) who have dry skin for about 2m+ already & always having tummy pain even after I burp him, also always prone to having flu/cough? I went to doctor they never really recommended me any cream or lotion or helped with anything much with the dry skin, and also I handle his flu with suction & nasal spray but I would like to avoid him having flu or such sickness... so I might want to try change formula milk. Currently using Dulac Dumex stage 1. Any recommendation for milk brand or this situation? Anyone with formula goat milk experience? Thanks in advance☺️