Hi i stayed in september 42 days and in december 70 days do you think if i leave 12 april back that they allow me for 60 days because i am gonna marry in peru in first week of june?

Depending upon your nationality , you are normally given permission to stay for up to 30 days on arrival for purposes of tourism. If you need to stay longer, you must ask for permission on arrival. Immigration officials can grant you up to 180 days a year as a visitor or tourist. You should be ok, but I would check with the Peruvian Consulate to see whether getting married alters things in any way.

i hope they will give me 60 because i am gonna marry the first week of june

I agree with crellston's advice to ask the Consulate. I don't know how things work in Peru, but in some countries there are penalties for overstaying the time you are allowed.

One more thing I don't know about Peru--does marriage automatically give you the right to stay indefinitely?

Also worth pointing out that the rules may vary depending upon your nationality which you don't mention

i am from the netherlands sorry i did not say

I am from the uk so probably the same. Here is the link to the UK Gov webpage for Peru. https://www.gov.uk/foreign-travel-advice/peru
I expect the Dutch government have something similar

we are allowed to stay 90/180 days

Hello Mohpa6, generally you can stay more than 30 days. If you have Dutch nationality, you can stay longer up to 180 days. So you will not have any inconvenience with your wedding.