I could use some advice please?

Today I ate a bowl of rice krispies for breakfast with semi-skimmed milk and then two slices of brown bread with pumpkin seeds in the bread with phillidealphia cheese however you spell it on one slice and some humous on the other slice.

For lunch I had a piece of chicken leg in sauce with thin slices of potatos with tomatos, cucumber and sweet corn as a salad with it.

For dinner I had some chilli con carni with brown rice and chickpeas.

I also had a pear and half a peach as snacks.

I’m in my late teens so I dunno if that’s okay for the day? Or is it too much? Can I eat a dessert?
I am underweight will this make me gain weight? I like being slim and I think I have a pretty fast metabolism
I am underweight will this make me gain weight? I like being slim and I think I have a pretty fast metabolism.