I want to sell the majority of my stock portfolio on the Robinhood app. How would I go about filing for taxes to minimize my loses? Some stocks have gained/loss

[oldschoolrunescape]

I have recently started using the Robinhood app in the last few months. I am looking to sell the majority if not my entire stock portfolio because I need the available cash. I have bought and sold many stocks for pennies of a profit. I feel like I made a huge mistake and am concerned that I have complicated the process of filing for taxes. 

[SweetieJean]

This and other similar articles may be helpful:

https://www.cohengrieb.com/year-end-tax-strategies-for-stock-market-investors