I really feel you on this, because choosing formula from the start can feel like such a big decision and it is completely okay. My girl was fully formula-fed from birth too, and honestly she grew up healthy and strong, so please do not feel any pressure or guilt about it.
When I was choosing, I looked out for whether the formula was suitable for newborns (stage 1), whether it had DHA and iron listed in the ingredients, and I also checked that it was easy on her tummy since some babies are more sensitive. I would also say talk to your PD early on, because they can recommend based on your baby's specific needs and weight gain, which gave me a lot of peace of mind lah.