I used this question as duplicate target, but noticed that another option is missing here.

If you don't like NotRequired (for example, if you have many required and many optional keys and don't want to repeat NotRequired many times) or don't want to bother with typing_extensions (rare case), you can tweak totality.

The following definitions of Main* are equivalent:

import sys
# You may also pick one without version check, of course
if sys.version_info < (3, 11):
    from typing_extensions import TypedDict, Required, NotRequired
else:
    from typing import TypedDict, Required, NotRequired


class Main1(TypedDict):
    foo: int
    bar: str
    baz: NotRequired[int]
    qux: NotRequired[str]


class Main2(TypedDict, total=False):
    foo: Required[int]
    bar: Required[str]
    baz: int
    qux: str


class _Main3(TypedDict):
    foo: int
    bar: str

class Main3(_Main3, total=False):
    baz: int
    qux: str


class _Main4(TypedDict, total=False):
    baz: int
    qux: str
    
class Main4(_Main4):
    foo: int
    bar: str

Here's PEP explanation of totality:

The totality flag only applies to items defined in the body of the TypedDict definition. Inherited items won’t be affected, and instead use totality of the TypedDict type where they were defined. This makes it possible to have a combination of required and non-required keys in a single TypedDict type.

Here's example of checking with definitions above:

Main1(foo=1, bar='bar', baz=2, qux='qux')
Main1(foo=1, bar='bar', baz=2)
Main1(foo=1, bar='bar')
Main1(foo=1, baz=2, qux='qux')  # E: Missing key "bar" for TypedDict "Main1"  [typeddict-item]
Main1(foo=1, bar='bar', who=None)  # E: Extra key "who" for TypedDict "Main1"  [typeddict-item]

Main2(foo=1, bar='bar', baz=2, qux='qux')
Main2(foo=1, bar='bar', baz=2)
Main2(foo=1, bar='bar')
Main2(foo=1, baz=2, qux='qux')  # E: Missing key "bar" for TypedDict "Main2"  [typeddict-item]
Main2(foo=1, bar='bar', who=None)  # E: Extra key "who" for TypedDict "Main2"  [typeddict-item]

Main3(foo=1, bar='bar', baz=2, qux='qux')
Main3(foo=1, bar='bar', baz=2)
Main3(foo=1, bar='bar')
Main3(foo=1, baz=2, qux='qux')  # E: Missing key "bar" for TypedDict "Main3"  [typeddict-item]
Main3(foo=1, bar='bar', who=None)  # E: Extra key "who" for TypedDict "Main3"  [typeddict-item]

Main4(foo=1, bar='bar', baz=2, qux='qux')
Main4(foo=1, bar='bar', baz=2)
Main4(foo=1, bar='bar')
Main4(foo=1, baz=2, qux='qux')  # E: Missing key "bar" for TypedDict "Main4"  [typeddict-item]
Main4(foo=1, bar='bar', who=None)  # E: Extra key "who" for TypedDict "Main4"  [typeddict-item]

You can fiddle with this in playground

You can mix required and optional values with inheritance and total. From the mypy docs

class MovieBase(TypedDict):
    name: str
    year: int

class Movie(MovieBase, total=False):
    based_on: str

Movie has required keys name and year, while based_on can be left out when constructing an object