MTX and Biologics whats the difference?

To start at the very beginning, I had a diagnosis of juvenile psorstic arthritis but went away when i was 19 after id had my big toe joints froze and bone trimmed to straighten them and stop them twisting. Only psoriasis present back then (25/30 years ago now) was very slight and on big toes. 13 years ago my scalp started off then 5 years ago my nails, 2 and a half years ago i got a patch of psoriasis on my knee and now i have it most places apart from feet hands and groin. My face has it on my forehead which is from my scalp when its bad. Despite the original juvenile diagnosis rheumo doesnt think my psoriasis is related despite the trainee rheumo i saw first telling me it was and calculations shows it to be moderately active. Came away comfused. Eventually I was treated with methotrexate but after ending up in hospital with sinal thrombosis and orbital cillilitus it was stopped. I then had the FAE but the side effects were awful and unlike the methotrexate didnt help so i was allowed back on mtx because results had been so positive and again 3 weeks in i had amazing results and no side effects and was feeling happy. Unfortunately my liver enzymes rose from 10 to 240 in a little over a week so was told to stop taking them once again and at my next appointment with dermo was told i needed 6 weeks off all meds as he thought my system needed time to recover from initial infections before trying something else as mtx was now out the question, he didnt want same problems and another treatment ruled out when it was my system that was the problem. He said it would be another systemic treatment as i had such fantastic results on my actual psoriasis despite other problems. A week later i recieved a copy of dermo letter to my doctor saying i had low egfr of 60 and was not a suitable candidate for cyclosporin and we would be discussing treatment options at our next appointment in particular apremilast or biological referal my be necessary. My appointment is next week and my skin is worse than when i started. My legs burn and itch constantly and all the places that i had it have flared back up plus lots of new spots on my upper stomach and bust and neck (was just on lower half of stomach before) im dreading going next week and having to wait longer to start a new treatment and it going even worse. My question is what is the difference between biologics or apremilast than what ive had already and would dermo be able to prescribe treatment or does his mention in his letter of referal for biologics mean i would need a referal to somebody else and have to wait all over again for an appointment and lastly what questions should i be asking when i see him. Sorry for long post, im just really struggling to understand and my dermo doesnt seem to give much info unless asked outright and have no idea what to even ask. Any help or advice 2woulf be appreciated thanks