Short answer, because there are a ton of details.
A 70A breaker does not connect directly to 15A or 20A receptacles (the "standard outlets").
There are basically two possibilities:
Subpanel
A 70A breaker can be connected, with appropriate wire, to a subpanel. A subpanel typically has a bunch of breakers, which can include 15A or 20A breakers that can be connected to 15A receptacles. This is commonly done either to serve a second building (garage, workshop, shed, barn, office) or to serve the main building if the main panel runs out of spaces for more breakers.
Beyond that, there are many details, depending on the specifics (type of panel, wiring method, power requirements, etc.)
Replace the Breaker
Sometimes you have an existing large breaker that is no longer in use but want to add a circuit for 15A or 20A receptacles. That is most common with, for example, an electric hot water heater that has been replaced with gas. But it can happen with other things as well. If that is how you ended up with a 70A breaker, you will need to replace it with a 15A or 20A breaker. The specifics will depend on the size of the wire and possibly some other factors. In addition, a 70A breaker would normally be 240V = 2 hots, so you would actually replace this with either a double 15A or 20A breaker or two separate breakers, again depending on a number of factors.