transfer to https from http

I’ve been given the following advice, but I’m afraid I haven’t a clue after 3 days !

Hi Alan,

you can fix this by installing the Better Search Replace plugin (https://wordpress.org/plugins/better-search-replace/) and replace http://www.adflags.eu with https://www.adflags.eu. That will update the links and should fix your issue. We recommend to create a backup of your database before doing this.

Mark.

I’m sure someone can point me in the right direction so I can get the ‘Not Secure’ removed from my site upon opening. You may have gathered I haven’t a clue without help.. Alan

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