I'm not certain how much information you already have. There is a great deal of info on the web. I don't remember whether I have worked with lentils, but I have done a lot of sprouting.
Any good glass jar will do. If you are working with lentils, you need something large enough to allow them to expand a bit. I use canning jars of several different sizes, depending what I'm sprouting. If you don't have any special jar tops used for sprouting - which you can get online or at a health food store - I have also used a rubber band wrapped around cheesecloth to top the jar. It just has to be a fabric which will allow some air to get in the jar and allow you to rinse the seeds a few times a day.
Put 3 times more water in your jar than the seeds. Maybe do about a quarter cup of seeds, but you decide. Again, once they start sprouting you need enough room in the jar for their growth. Soak the seeds the first day for 8-12 hours or overnight. I usually rinse my seeds at least once during that soak.
After the first soak, you are rinsing the seeds, but not putting water in the jar. Work hard to get as much water out of the jar with each soak and rinse. I try to find a way to lay the jar on its side and lift the back end so any water left on the seeds will find its way out. Keep the jar out of the sun. It should be in a shady spot with no sunlight. You will begin seeing them sprouting a day or 2 after first soak. I find that the larger the seed, the longer it takes to get that first sprout to show, so be patient. They are ready after the sprouts get an inch or 2 long, depending on how you like them. I do put my jars in sunlight on the last day, just to get them green enough.
Small seeds are a bit trickier to deal with and I won't go into it, but you can find good info online.
I also grow microgreens, which you might be interested in looking into later on. They are more work because they are grown, usually, in a bit of soil, but they are actually even more packed with nutrients than sprouts are, but they are more work.
I probably gave you more info than you needed, but you were kinda of vague. Good luck. I love sprouts and now I am going to get some going, thanks to your post.