If you have no prior experience in feeding babies, it will be wise to attend a feeding session with the child, to learn how exactly the baby has to be held, and treated, Some kids enjoy listening to good music while being fed, some need to be cuddled. What is imperative is that the baby has to be held up on the shoulder and burped after the feed or be ready for more gas and vomiting, even irritating colic.
For slightly older preschoolers, solid foods are good, but some may like it mashed. In any case, cut it into bite-sized pieces. But, at all ages, be ready for a mess at feeding times.