Incompatible with most current php

My site needs to update the php and before doing that I checked the plugin PHP Compatibility Checker, the cloudflare plugin is the only one that has the latest php version errors, follows the error:

ARCHIVE: /cloudflare/cloudflare-plugin-backend/src/SecurityUtil.php
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2 ERRORS FOUND 1 LINE FOUND
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16 ERROR The mcrypt_create_iv () function has been deprecated since PHP 7.1 and removed since PHP 7.2; Use random_bytes () or OpenSSL
16 ERROR The ‘mcrypt’ extension has been deprecated since PHP 7.1 and removed since PHP 7.2; Use openssl (preferred) or pecl / mcrypt once available
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ARCHIVE: /cloudflare/vendor/symfony/yaml/Parser.php
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0 ERRORS AND 1 WARNING FOUND 1 LINE FOUND
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72 ATTENTION The INI directive ‘mbstring.func_overload’ has been deprecated since PHP 7.2
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ARCHIVE: /cloudflare/vendor/symfony/yaml/Inline.php
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0 ERRORS AND 1 WARNING FOUND 1 LINE FOUND
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55 ATTENTION The INI directive ‘mbstring.func_overload’ has been deprecated since PHP 7.2
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How to solve this case?