World of Tanks Modern Armor

This achievement is pretty easy. It just takes a while to play the 100 games. It doesn't matter if you win or lose.

You can unlock a Tank Destroyer at tier 2 on all of the different nations tech trees except China and Japan. A Tank Destroyer is the symbol with a inverted triangle.

You can check your progress by going onto the stats page while in the garage for each TD you play. Or since you're on the Xbox one version you can check the percentage of the achievement when you press the button and scroll up to achievements.

This doesn't have to be done all in one TD.

The last of the three Tank Destroyer(TD) games played achievements, this is the longest and I would highly recommend trying out as many different TD's as you can to get a good taste of variety and see if you want to work through any other tank trees.
This achievement itself is quite easy, just time-consuming. At time of writing, every nation except Chinese and Japanese have Tier 2 TD's. TD's have a triangle by their Tier number.

Just start a game with your TD, if you get destroyed you can just go straight to your garage and pick another ready TD and play another match!