Some clinics have English and Chinese interpreters, and the probability of having a Chinese interpreter is higher. Your other option will be getting a personal interpreter and they usually go for about 30,000 won per hour. You can usually get these through the government referral. Another option is to use a medical tour agency. An agency is bit of hit or miss, they can save you time, energy, and make things easy with a possible financial savings depending upon their flexibility and network, but some could be priced at a premium, but if it's still affordable, then worth considering. But you have to screen, compare and do your homework with agencies as well.
Outside of PS most people can navigate daily life fairly well with no Korean. Download an an APP called BBB Korea, these are free on-demand phone interpreters to help with small daily conversations.
Word of caution on getting freelancer interpreter for PS or 'helpful' airbnb host who wants to translate for you at clinics, which often get recommended on forums. Sometimes these people are billed as helpful freelancers, but usually these people end up acting as covert and unlicensed brokers (people who get a hidden kick-back of your surgery without being an agency). Once you start talking to them, they may use a lot of nudges and ploys to win your confidence to arrest your judgment and implement a hidden agenda, or they may try to interfere with places you have picked. It's sad, but it happens.
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