The contact email you receive can’t be changed or edited, apart from the form field entries you have chosen. There’s no availability to rebrand it or use your own mail service.
There are other tools out there that will work better if you require more customisation. But the one that comes with Bootstrap Studio is an easy stand in, great for small personal sites.
You’ll need to use a third-party Form company. Take a look at https://www.machform.com/
One of the forum members here uses it, and speaks very highly of it.