how to tame a lovebird

I got a new lovie. It is four months old and the gender is unknown. He (i think?) is not tame at all. What are some tips for taming them? I would love to hear your experiences. I have not handled him yet but when the lady was putting him in the box for me he tried to bite her. For now I am just leaving him in the cage so he gets used to the surroundings and cage. I put him in my most busiest room so he gets to see us often. When and how should I begin the taming process?

For a bird to be grabbed by a huge unknown predator would be quite scary and the natural thing to do was to bite. So starting off, never grab your new Lovie!

I'll try make this a pretty short.
That's a good start, let him get used to where he is and try keep your distance until he is used to the people in the household. Unless it's for feeding/changing linings. This part you kind of have to break the boundaries but have a treat to distract him (I'll call refer to him as a he for now) if possible.
. Does he jump and cling to the opposite side of where you are? Try approach his cage until you see signs of distress, then stop. Let him get used to you at that distance. Once he's relaxed gradually get to the point where you can be by his cage and he's acting normally without any sense of fear.
Once this is done and you can approach his cage freely add in a plate or dish - whatever works best and every time you walk past try offer him a treat, or if he's really scared of hands being near him, drop it in the dish. Do this until he reacts calmly to hands being near his cage.
The next step is to start adding your hands in there. Start slow by placing it inside without moving it. Don't immediately rush to your bird but place it aside. Keep it there for 5-10 minutes each day at a constant time until your bird moves freely around the cage while giving your hand the "cold shoulder".
Once that's completed, try hold a millet and get him used to thinking that a "hand gives out treats". There's steps on how to incorporate a perch with the millet to get your bird to start stepping up all over youtube and online.
I personally do the longer way, I wouldn't immediately start offering millet because that was a great way for me to be bit. There's also videos showing you how to train an untamed/flighted bird in a week or days but it's always based on the bird (plus its background).
Your bird is the judge on when he's ready to be trained. Once he seems interested enough and is wanting to come outside, let him and let him explore around and give him that confidence boost.

Thank you for the advice! I will use it. I believe the bird (still doesn't have a name, any suggestions its a lutino) was on an all seed diet. I am feeding him lafeber nutri berries. It has 26% pellets in it and lots of good seeds. I also put some foraging diet in for him with lots of pellets so he can eat what he wants. I put a little bowl with pomegranate seeds, apple, kale, and carrots but he hasn't touched that. How do I show him that the fresh food is good? If he was tame I would offer it to him but he is not.