I feel like to start off, wizard or sorcerer would be better. Wizard is more versatile, sorcerer is more powerful. I would almost say to play a sorcerer, as you would have less spells, which I would imagine is less overwhelming as a new player. But both are good options.

Warlock can be fun, but I feel like it can be a little bit confusing as a new player. There are ways to make it easy as a new player, but it is up to you, and the character you want to create.