Agree with bunty. My advice would be:
1. Feed solids at least one hour after a milk feed. At this age, treat solids as "Activity" time, something for fun, as opposed to getting any significant nutrition from it.
2. Starting with cereal is still the gold standard, but lots of people skip cereal. I thought rice cereal was so boring, I just opted for baby oatmeal right away when I started DD2 on solids at about 5.5 mo.
3. Some of the most popular purees are pear, apple, sweet potato, squash, avacado. Some of the green veggies like peas or green beans don't get the LO's as excited, but some kids love them. You can also mix purees together, and that is just fine.
4. If your LO does not seem interested, pushes out with his/her tongue or gags a lot, try again in a few weeks. Or, maybe they just like purees and you can consider BLW at a later age.