Today is my wife's birthday, asI usual Ily buy a cake for her ion this date. Today is my wife's birthday, I usually buy a cake for her on this date.

'on this date' does not sound natural but is grammatically correct. I'd rephrase the whole sentence.

Today is my wife's birthday, as usual I buy a cake for her ion this date. Today is my wife's birthday, as usual I buy a cake for her on this date.

I don't know how to make a delicious cake like this one that I bought, for this reason I prefer to buy the cake than to try making by my owne one myself. I don't know how to make a delicious cake like this one that I bought, for this reason I prefer to buy the cake than to try make one myself.

We might want to say 'a cake as delicious as this one' but it depends on what exactly you mean.

I don't know how to make a delicious cake like thise one that I bought, f. For this reason, I prefer to buy the cake than try making byan make my own. I don't know how to make a delicious cake like the one I bought. For this reason, I prefer to buy than make my own.

I ordered the cake sending text messages to the cake storfrom the bakery by text message. I ordered the cake from the bakery by text message.

The sentence was totally intelligible but this is a more natural way to say it.

I ordered the cake by sending a text messages to the cbake storery. I ordered the cake by sending a text message to the bakery.

They asked me about what hour Iwhat time was I planning to takecollect the cake at and I scheduled to be there at 2pm. They asked me what time was I planning to collect the cake at and I scheduled to be there at 2pm.

They asked me about what hourwhen I was planning to takepick up the cake and, so I scheduled to be there at 2pm. They asked me when I was planning to pick up the cake, so I scheduled to be there at 2pm.