I fed my toddler cheese and yoghurt since around 8 months.
I would think anything is safe for them by toddler age. For yoghurt it is best to buy full fat plain yoghurt and you can add your own fruits since flavoured yoghurt is usually fat free with artificial sugar. I buy natural or Greek yoghurt. You can also buy baby yoghurt but in my opinion, it is a waste of money when babies can eat normal full fat yoghurt
As for cheese, hard cheeses are good for snacks, like Cheddar, Tasty or Colby (not sure if you have Tasty and Colby in Sg though). You can slice it up or if your toddler can chew well, into cubes. For cooking you can use Ricotta or Cottage Cheeses.
Hope it helps