I don’t know how to attach links. But if you use the search function and type bonding guides then you will find a lot of advice on this site. It can take a long time for the bond to happen - days, weeks...it won’t Happen in just few hours.
You also need to search for the guides on boar dominance and behaviour. Some behaviours are perfectly normal and are not a cause for alarm - mounting etc, you may even hear squealing but sometimes this can be submission rather than fear. If there is ever a full on blood drawing fight, then it means that they will never be able to live together.
Two boys need a lot of space, more than two sows do - how big is the cage you plan to keep them both in? - indoor, a 2x5 c&c is the recommended size for boars, or if outside, an equivalent size hutch (which is around 6ft). Also you will require two of all equipment, two bowls etc and open ended hidey houses so that no one piggy can get cornered by the other.
Unfortunately the risk with going out and getting a new piggy (rather than using a bonding service from a nearby rescue if you have one) is that you simply won’t know if their personalities are going to be compatible.
Good luck with them and I hope they become the best of friends!
