Assalamu Alaykum,
Really that questions cant be answered by us.
It is a major sin to miss a prayer, however it does not take a person out of Islam. He/She is still a Muslim. If you do not have a valid excuse for missing it, you cant make up for it. You must ask Allah for forgiveness and make sure that you can change your ways inshaAllah.
If you miss it and have a reason, then you should make up for it by praying it.
May Allah help us all remain firm and do our obligations inshaAllah.
Question: Is the one who leaves off a single (obligatory) prayer without a (Islaamically acceptable) reason taken out of the fold of Islaam?
Response: Concerning the one who intentionally left off a (obligatory) prayer without a (Islaamically acceptable) reason, then he is not taken out of the fold of Islaam unless he completely abandoned the (obligatory) prayer.
According to the majority opinion (of the scholars), whoever leaves off a single (obligatory) prayer, then he does not become a kaafir unless he abandoned it completely, (this being) in accordance with his (sal-Allaahu `alayhe wa sallam) saying:
((Between a person and kufr and shirk is the abandonment of the prayer)), [ Saheeh Muslim].
(He said: ((the prayer)) - implying abandoning the obligatory prayer completely)
...and he did not say ((leaving off a prayer)) (which would imply leaving off a single obligatory prayer);
Likewise, his (sal-Allaahu `alayhe wa sallam) saying:
((The covenant dividing us and them (i.e. the kuffaar) is the prayer. Whoever abandons it has committed kufr)), [at-Tirmidhee, an-Nasaa.ee, Ahmad, al-Haakim]
...and you are not required to make up that prayer, since you had left it without a (Islaamically acceptable) reason. Rather, you are required to repent to Allaah (Subhaanahu wa Ta'aala), and if you sincerely repented,
then Allaah (Subhaanahu wa Ta'aala) says:
{And He it is Who accepts repentance from His servants, and forgives sins, and He knows what you do}, [Soorah ash-Shooraa, Aayah 25]
Shaykh Ibn 'Uthaymeen
Fataawa Manaar al-Islaam - Volume 1, Page 131, Question No.99