depends on whether you have: webserver or a rootserver
webserver: ask your webhoster
rootserver: apt install php7.3
the hosting i have in ovh.com
; ovhconfig
;
; this file must be placed in $HOME/.ovhconfig or in $DOCUMENT_ROOT/.ovhconfig
;
app.engine
;
; values: php (php engine + opcache accelerator)
; notice: if php, a phpcgi engine will be activated as fallback (if previous engine crash)
;
; php:
; IMPORTANT: register_globals and magic_quotes_gpc are off for security
; php options .htaccess (like php version) are ignored
; phpcgi:
; IMPORTANT this is a fallback to previous system
; in this case
app.engine.version will be considered as AUTO and php version will be old system
; (meaning depending .htaccess or .phpX extension)
;
app.engine=php
;
app.engine.version specify version of your engine
;
; for php:
; default: 5.6
; for phpcgi:
; this option is ignored (= fallback in AUTO)
;
app.engine.version=5.6
;
http.firewall used to add application firewall (filter http requests)
;
; values: none | security
; default: none
;
http.firewall=none
;
environment
;
; values: production | development
;
; production:
; apache will maximise local cache
; mod_expires will grow up TTL of js, css, pdf, images, video, audio
; you can override it changing expiration explicitly in your .htaccess
; feel free to look on our guide.
; development:
; no expiration is added, files are not locally in cache,
; will speed up tests but decrease performances
;
; choosen environment will also be available in your variable ENVIRONMENT unix env
;
; default: production
;
environment=production
;
container.image
;
; values: legacy | stable | jessie.i386 | testing
;
container.image=stable
Not sure what the "Legacy" option is as I cannot understand the language your control panel is in, but it does appear that would let you run PHP 7.3, which means you shouldn't have any issues with the upgrade procedure.
