I’ve always purchased clear JETech cases from Amazon for less than $10 since my iPhone 8+ and always found them to be protective. Once they get dirty I just buy another one since they are pretty cheap!

JETech Case Compatible with iPhone 13 Pro Max 6.7-Inch, Shockproof Phone Bumper Cover, Anti-Scratch Clear Back (HD Clear) https://www.amazon.com/dp/B09BTDSM4Z/ref=cm_sw_r_cp_api_glt_fabc_4ME50YN6V0ARFKRG0CJ0?_encoding=UTF8&psc=1