My iPhone is overheating, battery draining, and force restart not working

A Force Restart will not address this from what I'm hearing, this sounds like major hardware failure that needs to be addressed at your nearest Apple Store's Genius Bar or Apple Authorized Service Provider. A Forced Restart only addresses software issues, not a leaking battery.

Genius Bar Reservation and Apple Support Options - Apple

Given the device is probably not new-out-of-box and if the thermal event was as ghastly as you describe it, there is a fair chance the battery died a horrible and irrecuperable death. Since no response can be achieved, only recourse is a trip to an Apple Store or authorized service provider for a definitive diagnosis.

If under warranty or AppleCare coverage, repair (i.e., battery replacement) could qualify as free or at least under a service fee much below the cost of the device. All cases of official 'repair' will entail an exchange of your device for a refurb of identical specs; you will need a backup of your stuff to recover full functionality.

Alternately, Apple an offers DIY choice if adventurous and very handy with tools and delicate procedures. Meaning you can get genuine parts and a loaner of the proper tools to do the deed.

To the AppleCare end-user, it is (sorta). You'll get charged just half an arm or leg and be handed a replacement, under "Accidental Damage". Note you have a limited number of times you can call one.

Thank you for participating in the Apple Support Community.

We want to make sure you reach the right team for help with your device. We recommend that you contact Apple Support directly. Depending on your region, you may be able to reach them here: Get Support.

This page should get you an idea if what to expect: iPhone Repair and Service - Apple Support

If there is water damage, warranty is dead and only "low" cost recourse would be AppleCare's 'Accidental Damage' clause if you have coverage. Also, if there is water intrusion, pretty sure the battery is the least of the damages. However these devices are water resistant and there is a fair chance this is not the cause.

i'm just not too sure what's the issue,

Bottom option: Other Damage.

Unless you still have physical SIMs, which you can swap, transferring an eSIM from one device to the next requires both to be operational, or else you will need assistance from your carrier. At least with mine, it entails no cost.

Liquid damage is not repairable at all.