'To await' means 'to wait for'. It is mostly used as a transitive verb and therefore we don't use a preposition after it unlike the verb 'to wait' which is intransitive and requires a preposition. 'A crowd of people awaited the train.' 'A crowd of people waited for the train.' 'Await' and 'wait for' can both also mean to be ready or waiting for someone or something. 'The same fate awaits us all' 'The same fate waits for us all.' The difference is mainly in the structure, although 'to wait for' is more common especially in spoken and informal English. Await is more formal, poetic and literary.

await is transitive - that means it can have a direct object - I await your reply BUT wait is intransitive and cannot have a direct object so a preposition MUST be added and it usually FOR in the context of awaiting. but you can also say "I waited from 6 until 6.30 but the bus never came" you don't say "I awaited the bus from 6 to 6.30 but it never came"