Simple budget for a tight month after 5 years as a hotel front-desk agent

My income is now a fraction of what it was as a hotel front-desk agent and I am trying to cover the essentials. I am in Birmingham, in case local advice matters. The rent is fixed and the car payment is high. Any apps or methods?

Thanks for writing this out. I went through something close to it last year, and it settled down once I kept a simple log of every call and form.