I think we’ve all been here at some point! Still better than letting recruits go to waste because your houses are full!
It looks like you will have access to higher level training camps soon enough. Those can burn through recruits better. Your Stronghold will let you get most of the key camps already. The good news is, you can take the recruits and food back out of that training camp if you have enough space in your storages for all the resources used for the training you are cancelling. Not such a big deal with what you’ve got going there, but cancelling a training that takes 70-100 recruits and loads of ham hurts! lol!
If you are a paid player, and plan on buying your heroes, you can get your camps up to lvl 11, and use 2 as Extra Low Cost (2 recruits, 1000 food), and the third for level 1 or 2, depending on how you are for wooden swords/backpacks. Sometimes when those are scarce you’ll be using 3rd camp at lvl 11 as well. Then focus on your forge to get items that will make your team smash things better!
If you’re a free player, then I’d recommend getting to camp 12 right away (guaranteed 3* heroes). Only stay there long enough to get a decent 3* hero of each colour, then move right on to camp 13! Camp 13 gives a chance of 4* heroes, and you’ll need them to keep growing in the game. It’s not a high chance, but it’s still a chance to get them. The 3 stars won’t help much once you have a decent team started. And camp 13 will toss out a minimum of a 3* each day.
After that some will say push your forge to get battle items that will let you play with bigger titans, and get more chances for improved loot to ascend your heroes. Others will recommend pushing on and do what you need to to get to camp 20 so you can start getting a chance at 5* heroes, and a much improved chance at 4* heroes. (It looks like camp 20 has around a 19% drop rate for 4s, and 5% drop rate for 5s. Follow the data collection here for up to date stats!) To get training camp 20 you’ll need all of your iron storages to lvl 18, and storage for a ton of food. for actual numbers check out the wiki.
Whatever you choose, pick your path and keep grinding! Always be building something. 
Good luck!