Hello, first of all your requested keyword was htaccess.
Although your project details don't mention it, I am presuming your server is running on Apache due to the keyword htaccess, if so, I have extensive experience with Apache and back end redirects using both mod_rewrite and mod_alias modules.
It is important that the redirects also return the correct redirect headers to the client web browser (and search engine bots if accessible), as well, optimisations and avoidance of redirect loops.
If you would like to contact me with some additional information, we can confirm and go from there.
As long as there are no complications in the server setup, this task can be completed in a short timeframe.
Thank you.