In your horoscope Sun is not in the 7th house but the 6th house , but in 7th Rashi or Sign that is Libra. You have Rahu, Mercury and Venus in the 7th house of marriage.
Anyway it is correct what you have read that Sun in 7th house causes Marital trouble, that is because Sun is a seperative planet. In your horoscope Sun is not in the 7th house so nothing to worry on that front.
You are asking if you will be able to conceive, listen for children both partners horoscopes are taken into consideration. I do not see you having any problem in having children because Jupiter is placed in the 5th house. As debilitated Ketu in Lagana aspects the 5th house , there may be delay in having children. Otherwise nothing to worry about. Make sure you and your partner do not have Nadi Dosha in your matching, it is the aspect that is taken into consideration when doing horoscope matching.