Review and fix broken links, update installation instructions, and e…

[niksseif]

Requested Changes in Issue:

• [x] Verify all the links on the page are working (you can use an integrity tool for this)
• [x] Update the PostgreSQL Brew installation instructions

Changes Made:

• All links have been updated.
• The PostgreSQL installation instructions have been updated.
• Additional instructions and explanations have been added to improve readability.

Questions:

• Please let me know if you have any suggestions or recommendations. Thanks 🙏

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