My phone keeps glitching and I’m not sure what to do!!

I have the iPhone 7 it worked perfectly until this fall. At first when I shut my phone down it wouldn’t turn back on only on to the white Apple screen then after a few hours it will turn back on. Then I notice that every time I click my home button it makes this really strange noise almost like a marble but not quiet. Then I noticed that my head phone won’t work ( I’ve used multiple pairs). There’s also been a lot of little glitches not sure what do I don’t have enough money to get a new one.