1) If you were, or are going to be, an independent contractor and report your income on schedule C, and you have expenses but no income, you don't do anything now. In the first year that you have self-employment income you can list all your prior expenses getting started as "startup expenses". Depending on the amount, they might be deductible all at once, or they might be partly deductible all at once and partly spread out over 15 years.
(This would normally apply to someone starting a business as a bakery, for example, where they have expenses before they open. But it certainly can apply to an actor or anyone else trying to be a schedule C self-employed person who has startup expenses.)
2) If you end up as a W-2 employee, as a qualified performing artist, you can only deduct expenses against income. You may be able to deduct 2020 expenses against 2020 income, if you are a qualified performing artist for 2020. But since you are not a qualified performing artist for 2019, you can't deduct your 2019 expenses, even if you get a job in 2020.
