starter problems

I have a Dodge Ram 150 it's a 1991 . I thouht it was a battery problem so I replaced the battery but it still not crenk it want even click.You can crank it but using a screwdriver on the starter so i've been told that the solenoid is bad can anyone tell me how to change this out on the starter

why change the starter if it cranks by jumping the solenoid that says the starter is good you should check the safety neutural switch or the relay or the ignition switch

my past experiance w/ starters is the solenoid usually atleast click when they r bad.

I tried a new relay but that did not fix my problem.So is there anyway that I can check the neutural switch and the ignition swith to see if they are good without replacing them with new ones