How to add plugins in custom wordpress theme?

with shortcodes and use text tool u can add where u want in custom wordpress website

1. Go to Plugins > Add New.
2. Type in the name of the WordPress Plugin or descriptive keyword, author, or tag in Search Plugins box or click a tag link below the screen.
3. Find the WordPress Plugin you wish to install.
   1. Click Details for more information about the Plugin and instructions you may wish to print or save to help setup the Plugin.
   2. Click Install Now to install the WordPress Plugin.
4. The resulting installation screen will list the installation as successful or note any problems during the install.
5. If successful, click Activate Plugin to activate it, or Return to Plugin Installer for further actions.

1. Go to Plugins > Add New.
2. Type in the name of the WordPress Plugin or descriptive keyword, author, or tag in Search Plugins box or click a tag link below the screen.
3. Find the WordPress Plugin you wish to install.
   1. Click Details for more information about the Plugin and instructions you may wish to print or save to help setup the Plugin.
   2. Click Install Now to install the WordPress Plugin.
4. The resulting installation screen will list the installation as successful or note any problems during the install.
5. If successful, click Activate Plugin to activate it, or Return to Plugin Installer for further actions.

Some WordPress Plugins require more steps to customize them. The Details ReadMe file should contain step-by-step instructions. After installation, this information is available on the Plugins Screen for each Plugin. If you are having problems with a WordPress Plugin, see the Troubleshooting section.

For information on how to install a WordPress Plugin manually, see our manual installation guide below.

Source

By changing the settings manually in the WordPress profile theme