Adding lines to robots.txt file

Hi,

I’d like to add the lines

User-agent: Googlebot
Allow: /

User-agent: Googlebot-Image
Allow: /wp-content/uploads/

User-agent: Bingbot
Allow: /

User-agent: Msnbot
Allow: /

to the robots.txt file.

I’ve read https://docs.wpslimseo.com/slim-seo/meta-robots-tag/?utm_source=settings_page&utm_medium=link&utm_campaign=slim_seo but as I’m not very experienced, I don’t understand how and where I can insert these lines of code.

Can you help me?

Thanks in advance.

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