I’m assuming that if there’s no attic (except for that small crawlspace) you must have a cathedral ceiling or some kind of structure where there’s no access to the roof framing. If this is the case, the only way to benefit from the soffit vents is when there’s an open channel inside of each rafter space between the soffit and the ridge vent. If that space has been stuffed with insulation, cutting vents in the soffit will not help you at all.
However, depending on your structure you might not be able to easily determine it, or this might be not possible at all without removing of the roof sheathing, taking apart soffits, interior walls, etc. If you can confirm that each of the rafter spaces has an open channel to allow air flow, the ideal situation would be to have a vent under each rafter space, or a continuous vent. That way you can eliminate air vent area calculations which may not be accurate in situations where there is no regular attic.
Unless you have some electrical conduit, outlet receptacles, lighting fixtures, or exhaust vents mounted in your soffits, there should be nothing inside them. I can’t guarantee it but it would be unusual.