Translation:I eat fruit as often as possible.
"agus is féidir" stands for "as is possible" in this instance coming after "chomh minic"
(g) (Comparative) (After chomh, oiread, ionann, amhail)
Déanfaidh mé é chomh maith ~ is féidir liom, I'll do it as well as I can.
Thug sé a oiread dó ~ a shásaigh é, he gave him enough to satisfy him.
Ní raibh a oiread ~ duine ann, there was not even one person there.
Bhí sé ionann ~ (a bheith) caite aici, she had almost spent it.
D'aithin mé é chomh luath ~ a chonaic mé é, I recognized him as soon as I saw him.
Labhair sé liom, amhail ~ dá mbeadh aithne aige orm, he spoke to me as if he knew me.
Agus is a conjunction that can be using in many different circumstances that typically use different words in English. "And" is just the most simple usage, and "as" is the most appropriate in this particular case - "while" and "as" are often interchangeable in English, but not in "as often as possible".
In English, "fruit" can be used as a mass noun, so even though you say "I eat apples" or "I eat bananas" using the plural, you say "I eat fruit" using what looks like the singular, rather than "I eat fruits".
In Irish, the plural torthaí is preferred, because there is no way to tell whether ithim toradh means "I eat fruit" or "I eat a fruit".
You don't apply the same logic to all foodstuffs. Ithim arán is "I eat bread", Ithim feoil, "I eat meat" but Ithim glasraí - "I eat vegetables" and Ithim milseáin - "I eat sweets" (plural) or, in American English "I eat candy" (singular/mass noun).