you can only tell if a spirit is lying if you know the spirit. if you want to protect yourself from demons and evil, cast a circle, or specify you only want good spirits. this normally keeps negative spirits away. does this mean you've called spirits who won't lie? no. good spirits can also lie. you could ask them something they don't want to talk about or don't know the answer to, feeling worried you'll stop talking to them, they'll lie.
or the spirit likes playing games. the spirit's not evil in this case either, they're bored, or that's just who they are. i've dealt with many spirits, Rori doesn't really want me to know him, so he'll lie and say things to see what my reaction will be. i've known him for so long, i know when he's lying.
personally, i don't know of any way you can get a spirit to only tell the truth. there are tells, like with anyone, to figure out what kind of spirit it is, or if it's lying, but for it to only speak the truth, no clue. and in regards to those questions, i've never met anyone [living or dead] who would answer yes to all three. only one spirit i've met would answer yes to loving the Holy Spirit, because she was catholic. being of the Holy Spirit, i think not.
i'd stick to the pendulum, and avoid the Ouija until you've had a few years experience with spirits. it's not evil, but the board is dangerous. it acts as a type of spiritual magnet, good or bad, they're drawn to it. the circle will keep the 'bad' ones out, but there's a problem with that as well from what i've seen. Rori can't get through the circle, so we have to wait for him to enter before we can close the circle. he's not evil, he's just not pure good either. he's kind of in the middle, like everyone really. keep in mind, there's spirits wandering outside the circle as a result of the boards use, so when opened, you'll have other spirits. one Samhain we kept opening and closing the circle because of how draining using the board is, as a result, any spirit would stand where we kept casting the circle. so we spoke with many different spirits that night.