Your payment frequency will depend on the partners you work with.
If you do TVDE, you can receive your money weekly.
If you want to work as a Delivery Driver with Correos Express, you can receive your money monthly.
All payments are made by bank transfer, after submitting the respective tax documents - invoice or green receipt - depending on your contribution status (if you are a tax entity or self-employed worker).
Be sure to consult more detailed information about Issuing and Submitting your invoice/receipt.
Consult the Obligations and Changes you may have throughout your professional career: VAT and IRS.