Please step way back and take a photo of the entire house and setting. People need to see the landscaping as well. Do you currently own this house? If so how do you use the sticking out add-on? Where is it located?

Does semi-d mean semi-detached? Is this what you're working with? Are you thinking of a covered or open porch? How would you use the porch? Just an entry landing or a sit and relax porch?

Can we see the whole building not just your side? I am always against have a duplex type exterior with 2 very different exterior s IMO they look bad. The building looks fairly modern to me and I have no idea where a porch would go and for what purpose. The area where I think the entry door is looks odd is it an enclosed space ?

What geographical area are you in? If UK, try https://www.houzz.co.uk/ for suggestions that will fit in with your neighborhood.

Found in your area some option

If it is windy, you probably won't want to be sitting out on the porch.

Walk the neighborhood and see what others have done. While I generally agree about the culled sides matching when we were in the UK this summer we noticed many were quite different.