My baby neck control is strong and stable but he is unable to sit. Can i still feed him solids? How do i let him 'sit up' ?

You can still feed baby solids. Most of my friends let baby rest in the bouncer and feed them. When they are able to sit supported then they will change to sit to booster seats. I started feeding my baby solids at 4 months and he sat in this booster seat i got from baby fair and slotted a pillow behind him. Time to time he will slide down or fall to the side. I will readjust and continue feeding.