We know that our Prophet (saw) saw Hell, just as he saw Paradise during his lifetime. al-Bukhaari and Muslim report from ‘Abdullaah ibn ‘Abbaas that the Prophet (saw) said concerning Salaat al-Khusf (eclipse prayer):
I saw Paradise and I reached out to take a bunch of its fruits. If I had managed to do so you would have eaten from it until the end of time. And I saw Hell, and I have never seen anything more terrifying. I saw that most of its inhabitants are women“. (Mishkaat al-Masabeeh, 1/480)

Imaam Ahmad reports from al-Mugheerah ibn Shu’bah that the Messenger of Allah (saw) said:
Hell was brought so close to me that I tried to blow its heat away from my face. I saw there the man with the stick with the crooked end, and one who had tended al-Baheerah (a she-camel let loose for pasture for idols, upon which nothing was allowed to be carried), and the man of Humayr and the woman who had imprisoned the cat“. (Saheeh al-Jaami’, 2/181 #1968)

Muslim reports from Jaabir (ra) that the Prophet (saw) said:
Paradise and Hell were shown to me. Paradise was brought close to me, so that I tried to take fruit from it but I could not reach it. Hell was shown to me, and was brought so close that I stepped back for fear that it would touch me. I saw a Humayr woman who was tall and black, being punished on account of a cat that she owned: she had tied it up, not giving it anything to eat or drink, or allowing it to eat of the vermin of the earth. I also saw Abu Thumaamah ‘Umar ibn Maalik being dragged by his trachea through Hell“. (Saheeh al-Jaami’, 2/298, #2394)

After people die they are shown, in al-Barzakh (the period between death and Judgement) their position in Paradise (if they are believers) or Hell (If they are disbelievers).