He lives next/ opposite door?
Does this bit of informal letter make sense ?
My neighbour lives just opposite me.try to find him in the morning.
When you are settled in my flat ,please water he plants.Besudes this , there I nothing else I have to tell you.

I need it to sound friendlier .
Thank you

Question

He lives next/ opposite door?
Does this bit of informal letter make sense ?
My neighbour lives just opposite me.try to find him in the morning.
When you are settled in my flat ,please water he plants.Besudes this , there I nothing else I have to tell you.

I need it to sound friendlier .
Thank you

Answer

It is understandable, but some of it is worded awkwardly.

I would say :

My neighbor lives just opposite me. You can look for him in the morning. After you are settled into the flat please water the plants. Besides this, there is nothing else you need to do. Welcome and have a good time!

Answer

It is a bit confusing. 
Here's an attempt at a change:
My neighbor lives opposite me. You can try to find him in the morning.
When you are settled in my flat, please water the plants. Besides that, there is nothing else to worry about!

Answer

My neighbour lives opposite me, you might meet him in the morning.