I will be pretty much reiterating some of what Criminal (poster above) has said, but on a new slate.
First of all: Are you basing the 1 mill off a certain amount of plat? If you have around 4000 plat, I would definitely recommend purchasing 200-300 energy sigils. Maybe 50 health sigils too.
Do not purchase an off-hand until you hit level 100, and then you can either buy the focus of the seer from the lux shop, or off another player for a little cheaper. There is no point purchasing any weaker off-hand, since you are pretty close to level 100.
Skills should be fire bolt, fire storm, fire attune all maxed. Reduce a few points from eshield and try and max incinerate. I would also recommend half maxing fire lure. This is pretty much the best DPS you will get from a fire build. (You can put shards instead of incinerate, but may as well use your fire lure as much as you can.
Gold rejuv ammy should be fine until you hit 150, where you can purchase the 500k talisman of the stars. Really no point upgrading to heroic ammy or the 100 lux amulet.
Get rid of the energy regen ring and slap on some good rings. With your budget, you should be able to get some royal or grand rings which will help a load.
For armour, move from warden to meteoric armour, and then to frozen once you hit 110. Don't bother buying any armour from shops, as the quest armour as you progress should be good enough. (Mage armour sucks pretty bad, so don't worry if your armour isn't that high)
For main hand, try and get your hands on a apprentice/master wand of the grove. This is a weapon from a rare spawn from the stonevale druids, and gives +2 (Apprentice) or +3 (Master) fire lure bonus, as well as a focus boost.
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If you don't want to purchase sigils, then buy the +10 energy bracelet. Once you hit 100, you can buy the +15 bracelet which will stack with the +10, and your energy should be fine. As well as the focus of the seer which gives 20 energy regen.
i would prefer master's grimoire over golden rejuv ammy untill hes 100, i think it'll help him even more
but, if u say golden rejuv ammy is good untill 150, then go with it
btw, something that u should know, if u find urself regening enough with heroic rejuv ammy or even golden, keep them, the heroic gives 35 armour bonus which is great for mages
oh and rings i forgot, as armo suggested, royals and grands, i wouldnt go with inc tho, inc isnt great for lower lvls lvling (tried it), but great for solo late lvls / bosses
ice shards is great as an extra dps skill, fast casting, fast cooldown, great dmg, medium energy cost, and dont forget casting ice lure at lvl 1
if u get fire lure rings u will have extra pts, i do use fire lure rings but i would prefer to have firestorm and firebolt ring (got myself a royal fireattune and royal flame -fire magic- already)
as for main hand, any rare wand is great, the grove one will add fire lure and focus (master one will add 35 focus and 3 firelure), but if ur using the ice shards one from eyes while having ice shards as an extra, it'll be better due the extra focus
and charm, try getting any firebolt charm, lesser (50 dmg lvl 65 req), greater (100 dmg lvl 115 req), royal (150 dmg lvl 135 req) and so on (ofc u will need to lvl for better than lesser), it'll be great, mostly with firebolt
any focus armour/firemagic armour is great
if u dont wanna buy quartz/topaz/diamond/opal/adamant armour, go with warden/met/frozen untill u get onyx-obsidian, onyx and obsidian give decent amount of firemagic and energy, not sure about how 'good' the armour is, and obsidian is onyx' upgrade, u could farm them for free but need higher lvl req, theres also spiritshadow but i find that pretty crap due the even lower armour (except gloves and boots, both give more focus than diamond)
as armo said, if u got 1M with plat, i would say 4k plat (unless u were planning to buy the 500k which is a waste and u got 8k plat)
invest some in energy sigils, maybe health sigils too idk how much tho, and waste all the plat on chests and SELL THEM ALL, i wouldnt trust my luck if i wasnt geared, sell them all, and try to be as expensive as u can (at least 15k-20k imo)