when key is turned sometimes car starts, and sometimes there is just a clicking coming from the drivers side, after a few tries the car starts. Is the problem the starter or the starter relay.
I doubt if you would ever hear the starter relay clicking from the driver’s seat. get under the Rodeo and lay your hand on the starter while someone twists the key to the crank position and feel for the clicking. If the battery is fully charged and the wiring is clean and tight and the starter clicks it needs replacing.
You have that IF right. Get the battery tested for free would be my step 1.
I would start with the battery and charging system. Many auto parts stores will do it for free. Most do a good job. They are hoping that you will buy any needed materials from them and it is not a bad idea to do so. Remember that those test are not 100% accurate nor is the advice they may offer, but it usually is not bad.
Personally I would prefer not sticking my hand onto any engine part when someone else is going to turn the ignition key, especially if it means being under the car or close to belts or other moving engine parts. We know you have a Rodeo, but we don't know what year or how many miles it may have on it, nor past history.