The estimated $6 trillion budget President Joe Biden will release on Friday will be the largest and most concrete outline of his priorities and ambitions for the next 10 years, from his $4 trillion proposals to modernize infrastructure and expand the social safety net to his funding requests for every federal agency and program.

Those familiar with the spending plan say that under his proposals, the national debt would exceed the record levels it reached at the end of World War II and equal 117% of economic output by the end...