Hello @Vision Of Coders !
Welcome to Microsoft QnA!
I see you need to make an estimate on the costs of Azure APP Service with PHP along with a MySQL DB
For the Small instance ( Max 10 GB) it will be around 80$ A month
I calculated 3 years Reserved for the DB
If you need more details please send your Question here !
I hope this helps!
Kindly mark the answer as Accepted and Upvote in case it helped!
Regards