during the time of sex as patr of foreplay can husband suck the navel of his wife,can he inser the tounge,fingure,penis in to the navel hole.
can husband kiss or suck the anal of his wife,can he insert his tounge into the vagina of his wife.
Forepaly is not only permissible between husband and wife but it is encouraged. The only thing one must avoid during foreplay is that which is Haram such as swallowing impurities (fluids from vagina, penis etc..)
Most of the things that are mentioned in your question such as sucking the navel of wife etc... are permissible. The above mentioned rule should always be kept in mind.
And Allah knows best.
Mufti Ikram ul Haq
Fatwa Center of America