After a bill has been introduced what happens next in the lawmaking process

The member have to debate it and then vote for it

Explanation:

the bill is debated, scrutinized and requesting for amendments in the lower house.

When the bill is accepted through the House of Representatives (lower house), the bill is then passed on to the upper house (Senate House) and further debated upon. If the majority of seats in the Senate House belongs to the Government Party, the bill can be easily passed through.

If the majority of seats belongs to the Opposition, the passing of the bill might get complicated. The debating of passing the bill is pursued and voted upon. If the bill needs amendments, it'll be passed back to the lower house and the entire process is repeated until the bill is passed to both the houses (bicameral legislature)

regarding the law, the 15th amendment was specifically designed thinking in the rights of black free men.

even though ratified on february 3, 1870, the promise of the 15th amendment would not be fully applied for a long time.poll taxes and literacy tests would allow southern states disenfranchise african americans. only in 1965 the voting rights for african americans would be actually able to vote in the south.

in 1965, president johnson signed the voting rights act, which aimed to overcome legal barriers that prevented african americans from voting as it was guaranteed by the 15th amendment to the u.s. constitution.

congress also has implied powers, which derive from the necessary and proper clause of the constitution and permit congress "to make all laws which shall be necessary and proper for carrying into execution the foregoing powers, and all other powers vested by this constitution in the government of the united states.