You used flash on the "lawn-with-leaves"-pic, didn't you? It changes the colours quite a bit ... and as much as I like green, I feel it is a bit ... erm ... off in that first one. Or is it a bright midday sun that gave you the effect?
The pizza is not sharp.
Nor is the close-up.
But practise will bring about the desired results.
In how far can you influence the settings on that camera, including ISO settings? You might need to go for higher ISOs in lower light situations to still get short enough exposure times to handhold those?