Installing SSL can usually be a very tedious process. Luckily for us, Certbot has an automated script to easily help us to get SSL/ HTTPS set up with a few command lines.

To start, install Certbot

sudo dnf install https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm
sudo dnf install certbot python3-certbot-nginx

Once Certbot is installed, automatically generate an SSL certificate by running this command. You will be prompted with several inputs to fill in.

certbot --nginx

[root@nginx ~]# certbot --nginx
[root@nginx ~]# certbot --nginx
Saving debug log to /var/log/letsencrypt/letsencrypt.log
Enter email address (used for urgent renewal and security notices)
(Enter 'c' to cancel): test@test.com

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Please read the Terms of Service at
https://letsencrypt.org/documents/LE-SA-v1.2-November-15-2017.pdf. You must
agree in order to register with the ACME server. Do you agree?
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(Y)es/(N)o: Y

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Would you be willing, once your first certificate is successfully issued, to
share your email address with the Electronic Frontier Foundation, a founding
partner of the Let's Encrypt project and the non-profit organization that
develops Certbot? We'd like to send you email about our work encrypting the web,
EFF news, campaigns, and ways to support digital freedom.
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(Y)es/(N)o: Y
Account registered.
Please enter the domain name(s) you would like on your certificate (comma and/or
space separated) (Enter 'c' to cancel): yourdomain.com
Requesting a certificate for yourdomain.com

Successfully received certificate.
Certificate is saved at: /etc/letsencrypt/live/yourdomain.com/fullchain.pem
Key is saved at: /etc/letsencrypt/live/yourdomain.com/privkey.pem
This certificate expires on 2022-04-02.
These files will be updated when the certificate renews.
Certbot has set up a scheduled task to automatically renew this certificate in the background.

Deploying certificate
Successfully deployed certificate for yourdomain.com to /etc/nginx/conf.d/nginx.conf
Congratulations! You have successfully enabled HTTPS on yourdomain.evoxt.com
We were unable to subscribe you the EFF mailing list because your e-mail address appears to be invalid. You can try again later by visiting https://act.eff.org.

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If you like Certbot, please consider supporting our work by:
* Donating to ISRG / Let's Encrypt: https://letsencrypt.org/donate
* Donating to EFF: https://eff.org/donate-le
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[root@nginx ~]#

With these set up, your domain's SSL setup should be complete.
 

Note: Your browser might still cache the old self-signed certificate, or the certificate will not update, hence still showing insecure SSL. To fix this, try clearing your browser's cache or try accessing your website with a different browser.
 

To check SSL status, try using this SSL Checker from Geocerts.