Welcome Humado,
I think that Pandorabots is a great place to get started and get familiar with AIML for free. You can share your bot with others for free if they are members (there is a small monthly fee to publish your bot so the public can see it.) You can take the AIML files you develop there and copy them to a platform that you create and host yourself later if you choose not to host your bot with them.
I am not sure that you need PHP and MYSQL to get started before you learn AIML. Pandorabots does not require PHP and MYSQL knowledge. I will post sample AIML code in a topic under the AIML category and you can check that out. I will provide you with a sample school news topic that let’s you specify news by day in advance and then the bot will respond each day with that days news when asked. You do not need a database and you do not need to edit the news AIML files each day.
Best Regards,
Alaric