The first question you need to ask, is do you really need to do this? Usually, if it can be done using a query, there is no reason to update the tables. As matter as fact, doing so could compromise the integrity of your database (what if after you update Table 2, a value in Table 1 changes - now the tables have discrepancies).
Usually, you only need to update the other table (instead of using a query) if you are trying to capture & store history (and not current values).
If you do need to update the table, take a look in Access' built-in help for Action Queries, specifically the "Update Query". This should give you details and examples on how to do it.