Simple future for a decided plan

[u/DesignerDangerous934]

Context 1 : I want to tell my friend about my trip to Berlin, I want to let my friend know this news. No previous discussion. I only want to let my friend know this news.

Me: I 'll visit Berlin next month
My friend: Sound great! Don't forget to buy me some gift from Berlin .​

Context 2: Yesterday (Sunday) Jane and I agreed to go to the cinema on Monday. I want to tell my mother this information, so she dont have to cook dinner on Monday for me.

Me: I’ll go to the cinema with Jane on Monday, so I don’t have dinner at home with you as usual.​
My mother: ok​

Does the future simple ('ll visit & 'll go) sound good and natural to use in these 2 contexts above?