Freelancers can generally deduct legitimate business expenses from their taxable income, which can meaningfully reduce what they owe, but the expense needs to be both ordinary and necessary for the work being performed.
Commonly deducted categories include a portion of home office costs, business software and subscriptions, professional development, a portion of internet and phone bills used for work, and travel directly related to client work.
Keeping organized records throughout the year, receipts, invoices, mileage logs, makes tax time significantly less stressful than trying to reconstruct everything in April. This article is general education, not personalized tax advice, and a tax professional can confirm what applies to your specific situation.