Sealing the terrace door. Which trade does this?

Hello everyone, attached is a picture of our patio door. Our neighbors have sealed this area on the outside with a black bitumen layer or something similar. Can someone tell me which craftsman performs this kind of work or can it be done by oneself?

Raw or the window maker

Then I'll ask there in a moment! Thanks

That alone is much faster and cheaper! Just last week I sealed my garage door this way. Went to the hardware store, got liquid plastic for building waterproofing, and then applied it with a small foam roller, done!

I had it done professionally by the roofer. It cost roughly 500€ gross for a lift-slide door (3m) and a double wing door (2m).

But can I keep water out with the sheet metal?

There will be a canopy over the door ... I think the liquid stuff would be better then ... The insulation is already installed, should I remove it first and then put it back on?