I am lost on a decision

Living in my home with mortgage. I’m a senior 70. I was making ends meet with OAS and CPP and my grandson lives with me since he was 6 but he will soon turn 18 and I won’t get CCB anymore. So that will significantly affect how I’m going to pay for everything. He’s applied for all kinds of jobs with no answer. He’s going to college in September. Any ideas on what I can do. I’ve already got in touch with real estate to sell but no senior living places will allow him to live with me. Other small homes are a fortune to buy.