There are many Qur'anic verses that state that the righteous will be
granted forgiveness on the day of judgment.
In Surah Ibrahim verse 41 ( O my Lord ! Forgive me and my parents and
the believers on the day of judgment).
Also in Surah al-Ma'idah verse 9: Allah (SWT), has promised those who believed and did good, that for them there is forgiveness and a great reward.
Also in Surah Aal-e-Imran verse 136 : For them reward is forgiveness from their Lord
and gardens with rivers flowing underneath.
Many other verses also state the righteous believers will be granted
forgiveness on the day of judgment.
Major sins are not like minors sins and a person who committed sins and repented is not like a person who insisted on committing sins until death. There are people who get
forgiveness for all their sins because of their sincere intentions and very
good deeds. But there are people who will get punished on the day of
judgment and after their punishment, they will be sent to Paradise.
It all depends upon the degree of sincerity and good deeds.