I would recommend talking to your pediatrician about it and get him in speech therapy. I have a niece that was speech delayed and therapy helped a ton. She is 4 now and you would know she was ever delayed. Early intervention is so important.
Definitely agree with talking to pediatrician and getting speech therapy. Child frustration with inability to communicate can make terrible twos ultra terrible
I recommend looking into if your local library (or one close enough) has the LENA Start program. It gives tips on increasing conversational turns and uses a device to track conversation. The biggest thing is to be talking to them and with them all the time. Try to read for 10 minutes a day. Turn on subtitles if you do tv time and play videos of things like ms Rachel that promote speech. If you already do these things it may be time to talk to your pediatrician and look into speech therapy. At this point my son is using full sentences that miss a couple of words or mess up the tense of the words. I can understand him 90-95% of the time and others can understand him around 40-60% of the time. He does not ask for diaper changes or admit to pooping, but he does tell me he’s hungry and needs food or wants to watch tv including what show and details of the episode he wants to watch. Speech began to ramp up around 18 months and got to this point between 24 and 26 months.