Dispose - Is it a verb?

Hey there folks. I have a strange doubt over here and I need a very very quick reply. The word Dispose.. Is that a verb?

So I had a question in my exam

The Garbage ______ [dispose] today evening.

So we have to put the correct tense using the word dispose. My answer is

The Garbage WILL BE DISPOSED today evening.

It may seem right. But as far as I know, when the 'be' verb comes, we have to add V+ing. Shouldn't we?

For Eg :

They WILL BE WRITING the homework tomorrow. So Here, ing has been added to the word WRITE since we used the BE verb.

So Why is that so the answer for my question is

The Garbage WILL BE DISPOSED today evening????

Why aren't we using Disposing instead of Disposed???

After Seeing this question I have a big doubt, whether the word DISPOSE is a verb???

Please Clarify me with an example.

And don't give me any definite definitions like Superlative Degree Comparative Modals and so on... Cause I don't know the real meaning of them.

If you give me a Definitive word for my question, then please give me a link too so that I can verify it and know about it.

Thanks