i can't get https to work

new at wordpress. web site i am working on did not have ssl (https) when it was built so i download https plugin installed it did the option as in the installation. i have one page i need it on. that page only had https secure post, secure child post no other boxes to check. when i go to the webpage there is no lock on the url bar to say it is a secure site. because it did not work i disabled the plugin went to setting general and changed home and site adress from http to https. i still do not get a lock on url bar to show it is secure

https://www.ads-software.com/plugins/wordpress-https/

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