Can I factory reset my iPhone 8 if I will have a computer if I forgot my passcode

I have an unlocked iPhone eight I just purchased from walmart.com and a jerk of a guy without me even having a chance to set it up put a pass code on it! I don’t even have an iCloud account set on it yet. I was searching different providers to see who could find the best package for me so I can get off his plan. Monday the joke of a guy Put a hammer or screwdriver into the screen of my other iPhone and this will be my back up I purchased not too long ago. I guess he’s upset. I already have a back up but I’m having to use Wi-Fi on another device to write this. I don’t have an iTunes account or in a cloud count on the device yet. And I don’t have a computer I sent the videos on YouTube is showing me to connect to. I don’t know what to do because I can’t even get into my iCloud account that I had on my phone because I had a 28 code recovery key and I had it hidden in my wallet and he stole it and I’m missing job opportunities and I don’t have my own mothers phone number memorized because she just got another one. I only know one person out All of my probably over 500 contacts. And that’s my daughter. I can’t reach out to anyone. I need some rice and some help please. How can I reset this new phone that you put this pass code on with only the side buttons or power button without a computer? Is that possible and how can I get into my iCloud account so I can get all of my contacts in my emails without my 28 Digit recovery key. I’m so frustrated I feel like giving up but I don’t know what to do. I’m so tired of this me and not him not letting me talk to my kids or my family or even go home for three years and tired of him trying to control me using my devices I paid for I have receipts for everything. He has no ride! Please someone help me remember the one screen with the iCloud account that I can’t get into. The whole screen is completely shattered white. Thank you and God bless.