To use as an education tax credit, you must pay tuition to a school that is accredited by the US Dept of Education to participate in federal student aid programs, and they must send you a 1098-T form showing tuition paid.
To use as a work expense, if you are a W-2 employee, that deduction was eliminated in tax reform.
If you are self-employed, you can deduct training expenses that maintain or improve your qualifications for your current job or career, but you can't deduct training expenses to meet the minimum qualifications to work at a new job or career.