Lure Fido in the crate with a treat to begin, toss the treat in and say “ in your house” once Fido is in, treat Fido well and then release Fido out by saying “all done” do this with the door open at first, moving to have the door closed and then locked
Use a high rate of reward( treat frequently) while Fido is in the crate, or give a chew or bone while they are in there, once the food stops completely ( pausing during treating is good practice), Fido comes out of the kennel. Once Fido is out, no more treats.
Build up the amount of time Fido is created, with rewards, while you are there, doing all sorts of activities, near the kennel.
Once Fido can stay in the kennel for a solid hour while you are home, move to leaving the room, then the house.
To prevent separation anxiety, give Fido treat before leaving the room or the house and wait until Fido is quiet and calm to let them out of the crate and have a low key hello. If Fido is really struggling to calm down, offer them a pee break ON leash or a drink of water and then put them right back in the crate with reward again, and then let them out for freedom once they are calm and quiet for at least 30 seconds, if they can't calm down, let Nadia know.
The biggest thing with crate training is that the kennel is a positive place, feed meals in there, treats, chews, bones, only good things happen in the crate. Low key hellos are important too, and pairing you leaving with food. But another huge factor is making sure Fido has enough brain stimulation while alone. Brain games, toys, food puzzles, and things of that sort can really help. As well as calming music and a comfy bed and maybe a blanket that smells like mum or dad!