Hello parents

My daughter will enter 4 mnth next two weeks, can i make her sit inside pillow chairs? After he reachs 4 ? With supports or its too early? Some ppl say it will make her bend her back letter and its nt good to sit , and question no. 2 can i start feeding her small things like slize of boiled apple, or those lists that are at youtube n google??

If. I can feed her so third question is .. how can i feed her if i cant let her sit 🤧🤧

Am so confused and i dont knw how to do whats the best for her 🥹🥹🥹