Custom URL redirect using htaccess on my wordpress site

I want to automatically redirect some URLs to a custom URL using htaccess code for my wordpress site.
example:

https://domain.com/best-chair-in-2021 => https://domain.com/best-chair-available-for-you
https://domain.com/best-bettery-in-2021 => https://domain.com/best-bettery-available-for-you
https://domain.com/best-computer-in-2021 => https://domain.com/best-computer-available-for-you
i have 100 of url like this

https://domain.com/best-chair-available-in-2021 => https://domain.com/best-chair-available-for-you
https://domain.com/best-bettery-available-in-2021 => https://domain.com/best-bettery-available-for-you
https://domain.com/best-computer-available-in-2021 => https://domain.com/best-computer-available-for-you
i have 100 of url like this

https://domain.com/best-chair-buying-guide-in-2021 => https://domain.com/best-chair-buying-guide-for-you
https://domain.com/best-bettery-buying-guide-in-2021 => https://domain.com/best-bettery-buying-guide-for-you
https://domain.com/best-computer-buying-guide-in-2021 => https://domain.com/best-computer-buying-guide-for-you
i have 100 of url like this

https://domain.com/best-chair-for-you-in-2021 => https://domain.com/best-chair-perfect-choose-for-you
https://domain.com/best-bettery-for-you-in-2021 => https://domain.com/best-bettery-perfect-choose-for-you
https://domain.com/best-computer-for-you-in-2021 => https://domain.com/best-computer-perfect-choose-for-you
i have 100 of url like this

I have attached my wordpress site current htaccess file