" No ", Allah will not punish us for our thoughts until we say it or believe it or apply it in our life. This is the Major Problem faced by many Muslims around the world. Bad thoughts come to their mind about different things but their intentions were not wrong, Allah knows the best.
If a thought comes to their mind and they will not apply it in life, surely there is will be no bad deed counted and Allah will not punish those but If the bad thoughts come in mind and he/she will apply it in life then surely he/she is doing the wrong thing and hence bad deeds are added in their account and Allah will also punish him/her for those bad deeds.
Abu Huraira reported: The Messenger of Allah (ﷺ) said:
"Verily, Allah has pardoned my nation for what occurs within themselves, as long as they do not speak of it or act upon it."