How to calculate electrical load of house

AAA,
Is this an academic question? Or are you planning
On a new or upgraded service?

The electrical code article 220 describes the load requirements
For just about everything you'll need. There is also an "annex" near the
Back of the book that provides many useful examples.

Here is a website, using the 2002 edition of the NEC, but shows the details that are needed to perform the calculations.

This should not be done by a DIY'er.

Single Family Dwelling Electrical Load Calculator